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SERVICE MANUAL MODELS Mercury/Mariner 40·45·50·50 Bigfoot (4-Stroke) With Starting Serial Numbers United States ..0G231123 1999, Mercury Marine 90-828631R3 MARCH 1999 Printed in U.S.A.
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Mercury Marine, that they have been trained in the recommended servicing procedures of these products which in- cludes the use of mechanics’ common hand tools and the special Mercury Marine or recom- mended tools from other suppliers.
It is important to note, during any maintenance procedure replacement fasteners must have the same measurements and strength as those removed. Numbers on the heads of the met- ric bolts and on the surfaces of metric nuts indicate their strength. American bolts use radial lines for this purpose, while most American nuts do not have strength markings.
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Service Manual Outline Important Information Section 1 - Important Information A - Specifications B - Maintenance Electrical C - General Information D - Outboard Motor Installation Section 2 - Electrical A - Ignition Fuel System B - Charging & Starting System C - Timing,Synchronizing &...
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ENGINE OIL CAPACITY Either 3 Quarts or 3 Liters ENGINE OIL SAE 10W-30 viscosity oil is recom- mended for use in all temperatures. SAE 25W-40 viscosity oil may be used at 25W-40 10W-30 temperatures above 40 F (4 C). +100...
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Engine Speed Limiter 6120 - 6280 rpm cdi Overheat Speed Control 1600 - 2400 rpm Engine Temperature Switch Above 131 F (55 C) No Continuity Below 104 F (40 C) Continuity Alternator Type Three Phase Alternator Output: CHARGING Electric Start 12 Volts - 10 Amps.
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SPECIFICATIONS Idle rpm (Out Of Gear) 45 hp 25 rpm 40/50 hp 25 rpm Idle rpm (In Forward Gear) 45 hp 25 rpm 40/50 hp 25 rpm Wide Open Throttle rpm (WOT) 5500–6000 rpm Range Main Jet Size 40/45 hp...
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SPECIFICATIONS Main Bearing Clearance 0.0005 - 0.0017 in. (0.012 - 0.044 mm) CRANKSHAFT Crankshaft Run-out 0.0012 in. (0.03 mm) Camshaft Dimensions Intake “A” 1.216 - 1.220 in. (30.89 - 30.99 mm) Exhaust “A” 1.213 - 1.217 in. (30.82 - 30.92 mm) CAMSHAFT Intake “B”...
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SPECIFICATIONS Valve/Valve Seat/Valve Guides: Valve Clearance (cold) Intake 0.006 - 0.010 in. (0.15 - 0.25 mm) Exhaust 0.010 - 0.014 in. (0.25 - 0.35 mm) Valve Dimensions: “A” Head Diameter Intake 1.177 - 1.185 in. (29.9 - 30.1 mm) Exhaust 1.020 - 1.028 in.
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Valve Lift 0.12 in. (3 mm) Pump Type Trochoid Engine Oil Pressure 30-40 psi at 3000 rpm (Warm Engine) Engine Oil Pan Capacity Either 3 Qts. or 3 Liters Oil Pump: Outer Rotor to Housing “a” 0.001 - 0.006 in. (0.03 - 0.15 mm) Inner Rotor to Outer Rotor “b”...
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SPECIFICATIONS 40/45/50 1997 and Newer models Gear Ratio 1.83:1 Gearcase Capacity 14.9 fl oz (440 mL) Lubricant Type Quicksilver Gear Lube-Premium Blend Forward Gear Number of Teeth 22 Spiral/Bevel 1997 AND NEWER GEAR HOUSING Pinion Gear (1.83:1) Number of Teeth...
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SPECIFICATIONS Propeller Information Charts Mercury/Mariner 50 (4-Stroke) 2.00:1 Non Bigfoot Wide Open Throttle rpm : 5500-6000 Recommended Transom Heights : 15”, 20”, 22.5” Right Hand Rotation Standard Gear Reduction : 2.00:1 Approx. Approx. Speed No. of Gross Boat Boat Range...
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SPECIFICATIONS Mercury/Mariner 50 (4-Stroke) 1.83:1 Non Bigfoot Wide Open Throttle rpm : 5500-6000 Recommended Transom Heights : 15”, 20”, 22.5” Right Hand Rotation Standard Gear Reduction : 1.83:1 Approx. Approx. Speed No. of Gross Boat Boat Range Propeller Diameter Pitch...
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SPECIFICATIONS Mercury/Mariner 50 (4-Stroke) 2.3:1 Bigfoot Wide Open Throttle rpm : 5500-6000 Recommended Transom Heights : 20”, 25” Right Hand Rotation Standard Gear Reduction : 2.31:1 Approx. Approx. Speed No. of Gross Boat Boat Range Propeller Diameter Pitch Blades Material Wgt.
MAINTENANCE Inspection And Maintenance Schedule To keep your outboard in the best operating condition, it is important that your outboard re- ceive the periodic inspections and maintenance listed in the Inspection and Maintenance Schedule. We urge you to keep it maintained properly to ensure the safety of you and your passengers and retain its dependability.
MAINTENANCE Every 100 Hours of Use or Once yearly, Whichever occurs first 1. Lubricate all lubrication points. Lubricate more frequently when used in salt water. 2. Change engine oil and replace the oil filter. The oil should be changed more often when the engine is operated under adverse conditions such as extended trolling.
MAINTENANCE Corrosion Control Anode Your outboard has control anodes at different locations. An anode helps protect the out- board against galvanic corrosion by sacrificing its metal to be slowly eroded instead of the outboard metals. Each anode requires periodic inspection especially in salt water which will accelerate the erosion.
MAINTENANCE Spark Plug Inspection Inspect spark plugs at the recommended intervals. 1. Remove the spark plug leads by twisting the rubber boots slightly and pull off. 2. Remove the spark plugs to inspect and clean. Replace spark plug if electrode is worn or the insulator is rough, cracked, broken, blistered or fouled.
MAINTENANCE Fuse Replacement – Electric Start Models The electric starting circuit is protected from overload by an SFE 20 AMP fuse. If the fuse is blown, the electric starter motor will not operate. Try to locate and correct the cause of the overload.
MAINTENANCE Lubrication Points Lubricate Point 1 with Quicksilver Anti-Corrosion Grease or 2-4-C Marine Lubricant with Teflon 1. Propeller Shaft – Refer to Propeller Replacement for removal and installation of the pro- peller. Coat the entire propeller shaft with lubricant to prevent the propeller hub from cor- roding and seizing to the shaft.
MAINTENANCE Lubricate Point 4 with light weight oil. 4. Steering Cable Grease Fitting – Rotate steering wheel to fully retract the steering cable end into the outboard tilt tube. Lubricate through fitting. Lubricate steering link rod pivot points with light weight oil. Steering Cable End Fitting WARNING...
MAINTENANCE Changing Engine Oil Engine Oil Capacity 3 U.S. Quarts (3.0 Liters) Oil Changing Procedure Pump Method 1. Place the outboard in an vertical upright position. 2. Remove dipstick and thread a Quicksilver Crankcase Oil Pump onto the dipstick tube. Pump out the engine oil into an appropriate container.
MAINTENANCE Changing Oil Filter 1. Place a rag or towel below the oil filter to absorb any spilled oil. 2. Unscrew old filter by turning the filter counterclockwise. 3. Clean the mounting base. Apply film of clean oil to filter gasket. Do not use grease. Screw new filter on until gasket contacts base, then tighten 3/4 to 1 turn.
MAINTENANCE Gear Case Lubrication When adding or changing gear case lubricant, visually check for the presence of water in the lubricant. If water is present, it may have settled to the bottom and will drain out prior to the lubricant, or it may be mixed with the lubricant, giving it a milky colored appearance. If water is noticed, have the gear case checked by your dealer.Water in the lubricant may result in premature bearing failure or, in freezing temperatures, will turn to ice and damage the gear case.
MAINTENANCE CHECKING GEAR CASE LUBRICANT LEVEL AND REFILLING GEAR CASE 1. Place outboard in a vertical operating position. 2. Remove vent plug. 3. Place lubricant tube into the fill hole and add lubricant until it appears at the vent hole. IMPORTANT: Replace sealing washers if damaged.
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MAINTENANCE DRAINING GEAR CASE 1. Place outboard in a vertical operating position. 2. Place a drain pan below outboard. 3. Remove vent plugs and fill/drain plug and drain lubricant. Vent Plugs and Fill/Drain Plug GEAR CASE LUBRICANT CAPACITY Gear case lubricant capacity is approximately 22.5 fl oz (655 ml). CHECKING LUBRICANT LEVEL AND FILLING GEAR CASE 1.
MAINTENANCE Storage Preparation The major consideration in preparing your outboard for storage is to protect it from rust, cor- rosion, and damage caused by freezing of trapped water. The following storage procedures should be followed to prepare your outboard for out-of- season storage or prolonged storage (two months or longer).
MAINTENANCE Positioning Outboard for Storage Store outboard in an upright (vertical) position to allow water to drain out of outboard. CAUTION If outboard is stored tilted up in freezing temperature, trapped cooling water or rain water that may have entered the propeller exhaust outlet in the gear case could freeze and cause damage to the outboard.
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GENERAL INFORMATION IMPORTANT INFORMATION Section 1C - General Information Table of Contents Serial Number Location ....1C-1 Power Trim System ......1C-9 Conditions Affecting Performance .
30% relative humidity at 77 F (25 C) tempera- ture and a barometric pressure of 29.61 inches of mercury. Summer Conditions of high temperature, low barometric pressure and high humidity all combine to reduce the engine power.
GENERAL INFORMATION Due to the horsepower/rpm characteristics of an engine, this will result in further loss of horsepower at the propeller with another decrease in boat speed. This secondary loss, how- ever, can be regained by switching to a smaller pitch propeller that allows the engine to again run at recommended rpm.
GENERAL INFORMATION CAVITATION Cavitation is caused by water vapor bubbles forming either from a sharp edge or angle on the gear case or from an irregularity in the propeller blade itself. These vapor bubbles flow back and collapse when striking the surface of the propeller blade resulting in the erosion of the propeller blade surface.
GENERAL INFORMATION Following Complete Submersion Submerged While Running (Special Instructions) When an engine is submerged while running, the possibility of internal engine damage is greatly increased. If, after engine is recovered and with spark plugs removed, engine fails to turn over freely when turning flywheel, the possibility of internal damage (bent connecting rod and/or bent crankshaft) exists.
GENERAL INFORMATION Propeller Selection For in-depth information on marine propellers and boat performance - written by marine en- gineers - see your Authorized Dealer for the illustrated “What You Should Know About Quicksilver Propellers...and Boat Performance Information” (Part No. 90-86144). For best all around performance from your outboard/boat combination, select a propeller that allows the engine to operate in the upper half of the recommended full throttle rpm range with the boat normally loaded (refer to Specifications).
GENERAL INFORMATION Propeller Removal/Installation Standard Models WARNING If the propeller shaft is rotated while the engine is in gear, there is the possibility that the engine will crank over and start. To prevent this type of accidental engine start- ing and possible serious injury caused from being struck by a rotating propeller, always shift outboard to neutral position and remove spark plug leads when you are servicing the propeller.
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GENERAL INFORMATION 4. Place a block of wood between gear case and propeller to hold propeller and remove propeller nut. 5. Pull propeller straight off shaft. If propeller is seized to the shaft and cannot be removed, have the propeller removed by an authorized dealer. 6.
GENERAL INFORMATION 8. Flo-Torque II Drive Hub Propellers Forward Thrust Hub Propeller Drive Sleeve Rear Thrust Hub Tab Washer Propeller Nut 9. Place propeller nut retainer over pins. Place a block of wood between gear case and propeller and tighten propeller nut to 55 lb-ft (75 Nm), aligning flat sides of the propeller nut with tabs on the tab washer.
GENERAL INFORMATION WARNING Avoid possible serious injury or death. When the outboard is trimmed in or out be- yond a neutral steering condition, a pull on the steering wheel or tiller handle in ei- ther direction may result. Failure to keep a continuous firm grip on the steering wheel or tiller handle when this condition exists can result in loss of boat control as the outboard can turn freely.
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GENERAL INFORMATION In rare circumstances, the owner may decide to limit the trim in. This can be accomplished by repositioning the tilt stop pins into whatever adjustment holes in the transom brackets is desired. WARNING Avoid possible serious injury or death. Adjust outboard to an intermediate trim po- sition as soon as boat is on plane to avoid possible ejection due to boat spin-out.
GENERAL INFORMATION Trim Tab Adjustment Propeller steering torque will cause your boat to pull in one direction. This steering torque is a normal thing that results from your outboard not being trimmed so the propeller shaft is parallel to the water surface. The trim tab can help to compensate for this steering torque in many cases and can be adjusted within limits to reduce any unequal steering effort.
GENERAL INFORMATION Cylinder Leakage Testing NOTE: Cylinder leakage testing*, along with compression testing, can help the mechanic pinpoint the source of a mechanical failure by gauging the amount of leakage in an engine cylinder. Refer to the manufactures tester instructions for proper testing procedures. * Courtesy of Snap-On-Tools Cylinder Leakage Tester (Snap-On-Tools MT324) NOTE: Spark plug hole is a 12 mm diameter.
6. Mix epoxy chromate primer (DP-40) with equal part catalyst (DP-401) per manufactur- ers instructions, allowing proper induction period for permeation of the epoxy primer and catalyst.
GENERAL INFORMATION CAUTION Be sure to comply with instructions on the label for ventilation and respirators. Us- ing a spray gun, apply one half to one mil even film thickness. Let dry, flash off for five minutes and apply another even coat of one half to one mil film thickness. This urethane paint will dry to the touch in a matter of hours, but will remain sensitive to scratches and abrasions for a few days.
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GENERAL INFORMATION DECAL APPLICATION 1. Mix ounce (16 ml) of dish washing liquid in one gallon (4 l) of cool water to use as wetting solution. NOTE: Leave protective masking, if present, on the face of decal until final steps of decal installation.
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OUTBOARD MOTOR INSTALLATION IMPORTANT INFORMATION Section 1D - Outboard Motor Installation Table of Contents Electric Fuel Pump ......1D-1 Wiring Harness .
Transom Opening “a” (Minimum) Single Engine (Remote) 19 in. (483 mm) Single Engine (Tiller) 30 in. (762 mm) Dual Engines 40 in. (1016 mm) Engine Center Line For Dual Engines “b” (Minimum) 22 1/2 in. (572 mm) Page 1D-2 90-828631R3 MARCH 1999...
OUTBOARD MOTOR INSTALLATION Lifting Outboard 1. Use lifting eye on engine. Steering Cable STARBOARD SIDE ROUTED CABLE 1. Lubricate the entire cable end with 2-4-C Lubricant with Teflon. 2-4-C w/Teflon (92-850736A1) 2. Insert steering cable into tilt tube. 3. Torque nut to specified torque. Nut Torque 35 lb-ft (47.5 Nm) 90-828631R3 MARCH 1999...
OUTBOARD MOTOR INSTALLATION Steering Cable Seal 1. Mark tilt tube 1/4 in. (6.4 mm) from end. Install seal components. 2. Thread cap to the mark. 1/4 in. (6.4 mm) 1/4 in. (6.4 mm) Mark Plastic Spacer O-Ring Seal Steering Link Rod 1.
OUTBOARD MOTOR INSTALLATION Installing Outboard – Thumb Screw Models WARNING Outboard must be fastened to boat transom one of two ways: 1. permanently fas- tened to transom with thumb screws, and mounting bolts (provided), or 2. secured to the transom using the optional outboard mounting kit (shown below). Should the outboard strike an underwater object or be steered into a sharp turn, failure to fas- ten outboard correctly to the boat transom with mounting bolts or optional mount- ing kit could result in outboard ejecting suddenly off boat transom causing serious...
OUTBOARD MOTOR INSTALLATION Installing Outboard – Non Thumb Screw Models 1. Attach (tape) engine mounting template (located in this manual) to boat transom. 2. Mark and drill four 17/32 in. (13.5 mm) mounting holes. 3. Install the outboard so that the anti-ventilation plate is in-line or within 1 in. (25 mm) be- low the bottom of the boat.
OUTBOARD MOTOR INSTALLATION Wiring Harness IMPORTANT: Warning Horn Requirement – The remote control or key switch assem- bly must be wired with a warning horn. This warning horn is used with the engine warning system. 1. Route wiring harness into bottom cowl. 2.
OUTBOARD MOTOR INSTALLATION Battery Cable Connections Single Outboards (–) Red Sleeve (Positive) Black Sleeve (Negative) Starting Battery Dual outboards 1. Connect a common ground cable (wire size same as engine battery cables) between negative (–) terminals on starting batteries. (–) (–) Ground Cable (Same Wire Size As Engine Battery Cable) –...
OUTBOARD MOTOR INSTALLATION Shift and Throttle Cable 45 and 50 hp Models Install cables into the remote control following the instructions provided with the remote con- trol. NOTE: Install the shift cable to the engine first. The shift cable is the first cable to move when the remote control handle is moved out of neutral.
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OUTBOARD MOTOR INSTALLATION 5. Push in on the cable end until resistance is felt. 6. While pushing in on the cable end, adjust the cable barrel to attain the measured dis- tance taken in Step 3. Adjust Cable Barrel To Attain The Measured Distance Taken In Step 3 Cable Barrel 7.
OUTBOARD MOTOR INSTALLATION 45-50 hp - Throttle Cable Installation 1. Position remote control into neutral. 2. Fit throttle cable through rubber grommet. Throttle Cable 3. Install throttle cable with retainer pin. Lock retainer pin in place. Throttle Cable Retainer Pin 90-828631R3 MARCH 1999 Page 1D-11...
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OUTBOARD MOTOR INSTALLATION 4. Move the throttle linkage arm down. Throttle Linkage Arm 5. While holding down the throttle linkage arm (“a” Step 4), adjust the throttle barrel until a 1/8 in. (3.2 mm) gap exists between the oval shaped boss and the cam. 1/8 in.
OUTBOARD MOTOR INSTALLATION 6. Fasten control cables with the cable latch. IMPORTANT: After installation, move the remote control handle a few times from the neutral position to the wide-open-throttle position in forward gear. Move handle back to neutral and repeat Step 6. Visually Check for the specified gap between the oval shaped boss and the throttle cam.
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OUTBOARD MOTOR INSTALLATION If boat tends to pull to the left, move the rear edge of the trim tab to the left. NOTE: Trim tab adjustment will have little effect reducing steering torque if the anti-ventila- tion plate is raised 2 inches (50 mm) or more above the boat bottom. Page 1D-14 90-828631R3 MARCH 1999...
IGNITION Ignition Description The ignition system uses CDI (Capacitor Discharge Ignition). This system provides quick voltage buildup and strong spark required for high power and high performance engines. The CDI ignition system does not incorporate mechanically operated points, therefor mak- ing this CDI unit virtually maintenance free.
IGNITION Trigger Coil Trigger Coil A single wound coil with magnet core mounted to one side of the stator mounting base. The trigger is positioned on the outside of the flywheel assembly and is charged when a raised boss on the flywheel passes the trigger/magnet winding. A pulse voltage is then sent to an (SCR) switch within the CDI unit.
(CDI) unit. The voltage is multiplied by the coil until it can jump the spark plug gap. The ignition coil will produce a high voltage current each crankshaft revolution, producing a spark at each cylinder at the same time (Waisted Spark Ignition). Ignition coil maximum output is approximately 40,000 volts. Page 2A-10 90-828631R3 MARCH 1999...
IGNITION Ignition Test Procedures Direct Voltage Adapter (DVA) WARNING DANGER – HIGH VOLTAGE/SHOCK HAZARD! Do not touch ignition components and/or metal test probes while engine is running and/or being “cranked”. STAY CLEAR OF SPARK PLUG LEADS. To assure personal safety, each individual spark plug lead should be grounded to engine.
IGNITION Ignition Troubleshooting WARNING DANGER - HIGH VOLTAGE/SHOCK HAZARD! Do not touch ignition components and/or metal test probes while engine is running and/or being “cranked”. STAY CLEAR OF SPARK PLUG LEADS. To assure personal safety, each individual spark plug lead should be grounded to engine. WARNING When testing or servicing the ignition system, high voltage is present.
IGNITION Ignition Diagnostic Procedures TROUBLESHOOTING TIP: With engine running, use inductive timing light to check spark advance of each cylinder as throttle is opened and closed. If timing advances and retards on each cylinder, ignition system is MOST LIKELY functioning properly. IMPORTANT: If outboard appears to have an ignition system failure, it is recom- mended that before beginning in-depth troubleshooting: Ensure that the engine is mechanically sound condition.
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IGNITION Weak Spark Condition Ground Connection at: (Low Primary Voltage) a - ignition coil b - (CDI) unit c - stator High Resistance To Ground at: a - stop/lanyard switch (water/corrosion) Weak Charge Coil (CDI) Unit Failure Ignition Coil/High Tension Lead(s) Spark Plug(s) Spark Plug Cap (Resistor) Timing Fluctuates...
When performing resistance tests, all component leads must be disconnected. Readings may very slightly due to temperature changes. Reading listed taken at 68 (20 C). TRIGGER COIL TEST OHMS 10 20 10 30 15 40 0 0 5 4 6 8 VOLTS DC AMPS METER TEST LEADS...
IGNITION STATOR TEST (IGNITION CHARGE COIL) OHMS 2 4 6 8 10 VOLTS DC AMPS METER TEST LEADS METER SCALE OHMS READING BLACK 272 408 272 - 408 LIGHTING COIL OHMS 2 4 6 8 10 VOLTS DC AMPS METER TEST LEADS METER SCALE OHMS READING BLACK...
IGNITION IGNITION COIL (PRIMARY) METER TEST LEADS METER SCALE OHMS READING BLACK 0 1 0 7 0.1 - 0.7 ORANGE BLACK SPARK PLUG CAP REMOVAL NOTE: High tension cables must have spark plug cap removed before testing. Cap contains 5k ohm resistor. IMPORTANT: To remove spark plug cap from high tension leads, turn cap counter- clockwise while applying slight outward pressure.
METER SCALE OHMS READING BLACK RXKΩ 3.5 - 5.2 THERMO SWITCH 57398 Thermo Switch 1. Check continuity of switch. Thermo Switch Continuity Check Above 131 F (50 C) No Continuity Below 104 F (40 C) Continuity Page 2A-18 90-828631R3 MARCH 1999...
IGNITION Flywheel Removal and Installation Flywheel Removal WARNING Engine could possibly start when turning flywheel during removal and installation. To prevent this type of accidental engine starting and possible serious injury, al- ways remove spark plug leads from spark plugs. 1.
IGNITION Flywheel Installation 1. Place flywheel key into slot. 2. Install flywheel. 3. Hold flywheel using flywheel holder (91-83163M). Apply oil to threads on crankshaft and tighten nut to the specified torque. FLYWHEEL WITHOUT LOAD RING & SPACER 53278 Flywheel Key Washer Apply Oil to Threads Flywheel Nut Torque...
IGNITION FLYWHEEL WITH LOAD RING & SPACER 53278 4-Stroke Outboard Oil (92-828000A12) Flywheel Key Washer Spacer Load Ring NOTE: Load Ring is for one time use and must be replaced if flywheel is removed. Flywheel Nut Torque 116 lb-ft (157 Nm) 90-828631R3 MARCH 1999 Page 2A-21...
IGNITION (CDI) Unit Removal and Installation 1. Remove and install the (CDI) unit as shown. 2. Refer to Section 2 Part D for wiring diagrams. 28341 (CDI) Unit Mounting Bolts (2) (CDI) Mounting Bolt Torque 100 lb-in. (11.3 Nm) Page 2A-22 90-828631R3 MARCH 1999...
IGNITION Rectifier Removal and Installation 1. Remove and install rectifier as shown. 2. Refer to Section 2 Part D for wiring diagrams. 55625 Rectifier Bolts (2) Rectifier Mounting Bolt Torque 100 lb-in. (11.3 Nm) Page 2A-24 90-828631R3 MARCH 1999...
IGNITION Stator Removal and Installation 1. Remove and install flywheel. Refer to Flywheel Removal and Installation. 2. Remove and install the stator as shown. 3. Fasten wiring together with sta-strap. 4. Refer to Section 2 Part D for Wiring Diagrams. 28338 Loctite “222”...
IGNITION Trigger Coil Removal and Installation 1. Remove and install the trigger coil as shown. 2. Fasten wiring together with sta-strap. 3. Set the air gap at .030 in. (0.77 mm) between the trigger and flywheel. 4. Refer to Section 2 Part D for wiring diagrams. .030 in.
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CHARGING AND STARTING SYSTEM ELECTRICAL Section 2B - Charging And Starting System Table of Contents Specifications ......2B-2 Starting System Components .
CHARGING AND STARTING SYSTEM Specifications Alternator Type Three Phase Alternator Output: CHARGING Electric Start 12 Volts - 10 Amps (Regulated) SYSTEM Lighting Coil Resistance (Grn - Grn) 1.2 - 3.2 Ohms @ 68 F (20 C) Lighting Coil Output Peak Voltage 8.9 Volts @ 1500 rpm P/N 50-825095 Top Mounted Electric Start:...
CHARGING AND STARTING SYSTEM Starter Motor (S/N-0G472132 & Below) Liquid Neoprene (92-25711--2) 2-4-C w/Teflon (92-850736A1) 4-Stroke Outboard Oil (92-828000A12) Page 2B-4 90-828631R3 MARCH 1999...
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CHARGING AND STARTING SYSTEM Starter Motor (S/N-0G472132 & Below) TORQUE REF. REF. QTY. DESCRIPTION lb-in. lb-ft STARTER MOTOR RETAINER GEAR BRACKET–front METAL O RING WASHER KIT ARMATURE STATOR SPRING BRUSH HOLDER ASSEMBLY BRUSH SET WASHER BRACKET–rear BOLT BOLT (M8 x 45) 22.5 31.0 BOLT (M8 x 30)
CHARGING AND STARTING SYSTEM Battery Recommended Battery A 12 volt battery with a minimum rating of 465 marine cranking amps (MCA) or 350 cold cranking amps (CCA). For operation below 32 F (0 C) a rating of 1000 Marine Cranking Amps (MCA) or 775 Cold Cranking Amps (CCA) is recommended.
CHARGING AND STARTING SYSTEM Battery Charging System Description (10 Ampere) The battery charging system components are the stator lighting coils, rectifier/regulator and battery. Alternating current (generated in stator lighting coils) flows to the rectifier/regulator, which changes the alternating current to a regulated direct current for charging the battery. Wiring Diagram (10 Ampere) Blk = Black Blu = Blue...
CHARGING AND STARTING SYSTEM Alternator System Test (10 Ampere Stator) 1. Check battery voltage at battery with engine running. 2. If battery voltage is above 14.5-15.0 volts, replace voltage regulator/rectifier. Check con- dition of battery as overcharging may have damaged battery. 3.
CHARGING AND STARTING SYSTEM Stator Ohms Test (Alternator Lighting/Charging Coil) NOTE: Stator can be tested without removing from engine. 1. Disconnect the three wire (stator harness plug). 2. Use an ohm meter and perform the following test. NOTE: When measuring the resistance of 10 ohms or less using a digital ohm meter, if the correct measurement cannot be obtained, place the meter selector to a lower resistance measurement.
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CHARGING AND STARTING SYSTEM Rectifier/Regulator Diode Test GRN/WHT GRN/WHT Voltage Regulator/Rectifier Test Point - BLK Test Point- GRN (1) Test Point- GRN (2) Test Point- GRN/WHT Test Point- RED IMPORTANT: When performing a diode test on the rectifier/regulator, use only a digi- tal meter with the capability of selecting a diode inspection mode.
CHARGING AND STARTING SYSTEM Starting System Components The starting system consists of the following components. 1. Battery 2. Starter Solenoid 3. Neutral Safety Switch 4. Starter Motor 5. Ignition Switch Description The function of the starting system is to crank the engine. The battery supplies electrical energy to crank the starter motor.
CHARGING AND STARTING SYSTEM Starter Solenoid Test 1. Inspect starter solenoid for cracks, loose terminals or loose terminal lead connections. 2. Connect ohm meter between terminals of starter solenoid. 3. Connect the BLACK lead from solenoid to battery negative (–) terminal and momentarily connect the BROWN lead to the positive (+) terminal of battery.
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CHARGING AND STARTING SYSTEM The following “STARTING CIRCUIT TROUBLESHOOTING FLOW CHART” is designed as an aid to troubleshooting the starting circuit. This flow chart will accurately locate any exist- ing malfunction. Location of “TEST POINTS” (called out in the chart) are numbered in dia- gram below.
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CHARGING AND STARTING SYSTEM * Battery Voltage TEST 2 a. Disconnect BLACK ground wire(s) from Test Point 2. b. Connect voltmeter between common engine ground and Test Point 2. No voltage reading; c. Turn ignition key to “Start” position. proceed to TEST 3. 12 Volt Reading* TEST 3 a.
CHARGING AND STARTING SYSTEM Starter Motor P/N 50-825095 (Top Mounted) Removal CAUTION Disconnect the battery leads from the battery before removing starter. 1. Disconnect the battery leads from the battery. 2. Disconnect the ground cables. 3. Remove starter mounting bolts. 4.
CHARGING AND STARTING SYSTEM Disassembly 1. Press down the pinion stopper and remove the circlip. Remove the pinion. Pinion Pinion Stopper Circlip (discard and use new circlip on assembly) 2. Remove through bolts and disassemble starter motor assembly. Cleaning and Inspection 1.
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CHARGING AND STARTING SYSTEM BRUSH HOLDER 10. Inspect brushes for wear. Replace brush holder if not within specifications. Wear Limit - 0.47 (12.0 mm) 11. Ohm test the brush holder. The positive (+) brushes should not show continuity to brush holder.
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CHARGING AND STARTING SYSTEM 14. Measure the armature shaft for deflection. If the armature has greater than 0.002 in. (0.05 mm) deflection, replace armature. Armature V-Block Dial Indicator Gauge 15. Measure the commutator diameter. Replace if not within specification. MIN. Commutator Commutator Diameter Wear Limit - 1.22 in.
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CHARGING AND STARTING SYSTEM 17. After cleaning, ohm test each segment of the commutator as shown. If ohm test reading is other than listed, replace the armature. ARMATURE COIL CONTINUITY METER TEST LEADS METER READING SCALE BLACK CONTINUITY CONTINUITY SEGMENT SEGMENT Commutator Lamination...
CHARGING AND STARTING SYSTEM Reassembly 1. Place washers on the armature shaft. 2. Place armature shaft into front bracket. Washer (Fiber) .08 in. (2.0 mm) Thick Washer .04 in. (1.0 mm) Thick Washers (Use as Required) (Adjust Washers Until 0.05 - 0.010 in. (0.05 - 0.25 mm) Axial Play Exist on the Armature Shaft Front Bracket 1.
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CHARGING AND STARTING SYSTEM 4. Install stator onto the front bracket. Align Projection with cut in the cover. NOTE: Make sure stator is installed so magnets are positioned correctly. 3/4 in. (19.0 mm) 53833 O-Ring Seal Space Between Magnets and Stator End Align Projection with Cut in the Bracket Stator Front Bracket...
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CHARGING AND STARTING SYSTEM 6. Install rear bracket. Insert wire insulator into slot and align projection with cut in bracket. 53832 O-Ring Seal Wire Insulator Align Projection with Cut in the Rear Bracket Rear Bracket 7. Fasten brush card to rear bracket with two screws. 8.
CHARGING AND STARTING SYSTEM Starter Motor P/N 50-834749 (Side Mounted) Removal WARNING Always disconnect the battery and remove spark plug leads from spark plugs be- fore working on motor. 1. Disconnect battery leads from battery. 2. Disconnect BLACK cable. 3. Remove 3 bolts. 4.
CHARGING AND STARTING SYSTEM Disassembly 1. Remove 2 thru bolts and commutator end cap, taking care not to lose brush springs. Thru Bolts Commutator End Cap Brush Springs 2. Press down the pinion stopper and remove the circlip. Remove the pinion. Pinion Pinion Stopper Circlip (discard and use new circlip on assembly)
CHARGING AND STARTING SYSTEM Cleaning and Inspection 1. Clean all motor parts. 2. Check pinion teeth for chips, cracks or excessive wear. 3. Replace the drive clutch spring and/or collar, if tension is not adequate, or if wear is ex- cessive.
CHARGING AND STARTING SYSTEM Testing ARMATURE TEST FOR SHORTS Check armature for short circuits by placing on growler and holding hack saw blade over armature core while armature is rotated. If saw blade vibrates, armature is shorted. Re- check after cleaning between commutator bars. If saw blade still vibrates, replace armature. ARMATURE TEST FOR GROUND 1.
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CHARGING AND STARTING SYSTEM CHECKING POSITIVE BRUSHES AND TERMINALS 1. Connect ohmmeter (R x 1 scale) leads between positive brushes. 2. Ohmmeter must indicate full continuity (zero resistance). If resistance is indicated, check lead to positive terminal solder connection. If connection cannot be repaired, brushes must be replaced.
CHARGING AND STARTING SYSTEM Brush Replacement IMPORTANT: Replace brushes that are pitted or worn to less than 1/4 in. (6.4mm) in length 11660 Positive (+) Terminal Long Brush Lead Push Lead Into Slot Insulating Washer Flat Washer Lock Washer 11656 Positive (+) Brushes Negative (–) Brushes Brush Holder...
CHARGING AND STARTING SYSTEM Reassembly 1. Lubricate helix threads and drive end cap bushing with SAE 10W oil. 2. Install the pinion, spring, and pinion stopper onto starter shaft. 3. Place circlip into groove on shaft. 4. Press the pinion stopper over the circlip. IMPORTANT: Install new circlip for reassembly.
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CHARGING AND STARTING SYSTEM 5. Construct a brush retainer tool as shown. Brush Retainer Tool Layout (Full Size) 18-Gauge Sheet Metal METRIC SCALE 3” = 76.2mm 2” = 50.8mm 1-3/4” = 44.5mm 1-11/16” = 42.9mm 3/4” = 19.1mm 1/2” = 12.7mm Brush Retainer Tool Side View (Full Size) 90-828631R3 MARCH 1999 Page 2B-33...
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CHARGING AND STARTING SYSTEM 6. Place springs and brushes into brush holder and hold in place with brush retainer tool. 7. Lubricate bushing with one drop of SAE 10W oil. DO NOT over-lubricate 11661 Brush Retainer Tool Bushing 8. Position armature into starter frame so that commutator end of armature is at end of starter frame where permanent magnets are recessed 1 in.
CHARGING AND STARTING SYSTEM Installation 1. Secure starter to block with 3 bolts. Torque bolts to specified torque. Secure NEGATIVE battery lead to block with bottom bolt. 2. Connect battery lead (BLACK cable) to starter. Torque attaching nut to specified torque. 55626 Black Cable Bolts (3)
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6120 - 6280 rpm C.D.I. Overheat Speed Control 1600 - 2400 rpm Engine Temperature Switch Below 131 F (55 C) No Continuity Above 104 F (40 C) Continuity Idle rpm (Out Of Gear) 45 hp 25 rpm 40/50 hp 25 rpm...
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Idle rpm in Forward Gear 45 hp 25 rpm 40/50 hp 25 rpm 4. Rev engine 2 or 3 times and allow to idle for 15 seconds. If the engine holds a stable idle condition, then no other adjustments are necessary.
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Intake Manifold Hose Adaptor (4) Filters (35-18206) Carburetor Tuner (91-809641A1) CAUTION To avoid the possibility of drawing mercury from the vacuum gauge into the engine, do not run engine at high rpm speed and avoid rapid throttle deceleration (high vac- uum situations). SYNCHRONIZING CARBURETORS 1.
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TIMING, SYNCHRONIZING, & ADJUSTING NOTE: Keep engine speed set at approximately 1000 rpm in neutral while synchronizing carburetors. Idle rpm Screw 4. Read the vacuum of cylinder #4. It’s not important to be at any specific vacuum setting. 1 2 3 4 Vacuum Reading Cylinder #4.
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TIMING, SYNCHRONIZING, & ADJUSTING NOTE: Keep viewing the tachometer, as the engine rpm may fluctuate during adjustments. Keep adjusting the idle rpm screw in order to keep the engine speed at approximately 1000 rpm. Example If the vacuum reading of Cyl. #4 is 32 cm, then adjust carburetor screws 3, 2, and 1 to obtain the listed averaged vacuum values at the other cylin- ders.
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TIMING, SYNCHRONIZING, & ADJUSTING Idle Mixture Screw Adjustment NOTE: Idle mixture screw adjustment is required when stable idling could not be obtained after synchronization. NOTE: The engine should be completely warmed up for the adjustment. Correct adjust- ments can not be obtained in a cold condition. NOTE: The idle mixture screw is: Adjustable: -All model years for the 45 hp version...
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TIMING, SYNCHRONIZING, & ADJUSTING DYNAMIC ADJUSTMENT (45 HP MODELS) NOTE: CO metering equipment has to be used to accurately adjust the idle mixture screws within the exhaust emissions limits. 1. Remove four plugs from the exhaust manifold. 2. Install a exhaust manifold hose adaptor (91-809905A1) in each plug hole. Exhaust Manifold Plugs (4) Exhaust Manifold Hose Adaptor (91-809905A1) Plug - Hose Adaptor...
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TIMING, SYNCHRONIZING, & ADJUSTING Dashpot Adjustment NOTE: Dash-pot adjustment is required when engine stalls upon quick deceleration. NOTE: The engine should be completely warmed up for the adjustment. Correct adjust- ments can not be obtained in a cold condition. 1. Pull out the retarder plunger fully. 2.
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To prevent personal injury from spinning flywheel, Do Not attempt to remove fly- wheel cover or place hands on top of cover when checking ignition timing. Timing Specifications 40/45 Full Retarded - 5 B.T.D.C. Full Advanced (2500-3000 rpm) - 25 B.T.D.C.
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2. Slowly increase the engine rpm while watching the ignition timing marks. The timing should increase to the maximum timing specification “Full Advance” at approximately 2500-3000 RPM. (If not within specification window, refer to Diagnostic Test Procedures Section 2A.) 50 hp 40/45 hp Timing Mark (Full Advance) 90-828631R3 MARCH 1999 Page 2C-11...
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WIRING DIAGRAMS ELECTRICAL Section 2D - Wiring Diagrams Table of Contents Electric Start Wiring Diagram ....2D-2 Commander 3000 Panel Mount Control ..2D-6 Tiller Handle Wiring Diagram .
WIRING DIAGRAMS Electric Start Wiring Diagram PTC Heater Solenoid Coil CDI Unit Trim Down Relay Trim Up Relay Starter Trim Pump 20 Amp Fuse Starter Relay Voltage Regulator Cowl Mounted Trim Switch Stator Trigger Oil Pressure Switch Ignition Coil Remote Wiring Plug Spark Plugs Block Temperature Switch Thermo Switch...
WIRING DIAGRAMS Tiller Handle Wiring Diagram YEL/RED BLK/YEL BLK/YEL BLK/YEL BLK/YEL YEL/RED YEL/ TAN/BLU BLK = Black BLU = Blue GRY = Gray GRN = Green PUR = Purple RED = Red TAN = Tan YEL = Yellow Neutral Start Switch Auxiliary Harness Not Used Horn...
WIRING DIAGRAMS Commander 3000 Panel Mount Control BLK/YEL BLU/WHT Â Â Â Â Â Â Â Â Â GRN/WHT YEL/RED BLK = Black YEL/RED BLU = Blue BRN = Brown GRN = Green GRY = Gray PUR = Purple YEL/RED RED = Red TAN = Tan WHT = White...
WIRING DIAGRAMS Power Trim Switch Wiring Diagram GRN/WHT LT. GRN/WHT LT. GRN/WHT BLU/WHT LT. BLU/WHT LT. BLU/WHT GRN = Green BLU = Blue RED = Red WHT = White Trim Switch Starter Relay 90-828631R3 MARCH 1999 Page 2D-7...
WIRING DIAGRAMS Remote Wiring Harness Connection to Engine ELECTRIC START REMOTE CONTROL MODEL 1. Route the remote wiring harness to the back of the engine block as shown. Remote Wiring Harness 2. Plug the remote wiring harness into the engine wiring harness connector. Push the har- ness connection into the holder.
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FUEL PUMP FUEL SYSTEM Section 3A - Fuel Pump Table of Contents Specifications ......3A-1 Fuel Pump Disassembly .
FUEL PUMP Fuel Pump Operation 1. The fuel pump is a diaphragm pump which is mechanically driven off of the rocker arm. 2. The black mounting block (insulator) and the two outlets on the fuel pump help prevent vapor lock. 3.
FUEL PUMP Fuel Pump Removal 1. Remove sta-straps from fuel lines. IMPORTANT: The hose fittings on the fuel pump can break if you try twisting or pull- ing the hoses off. Remove hoses by slowly prying off the hoses using a small screw- driver.
FUEL PUMP Fuel Pump Disassembly 1. Remove screws to separate pump cover, cover seal, and diaphragm, from pump body. 28378 Screws (4) Pump Cover Cover Seal Diaphragm Pump Body Nuts (4) 2. Rotate plunger to line up slots. 53615 Slots Offset Slots Aligned 3.
FUEL PUMP Cleaning/Inspection/Repair 1. Inspect fuel filter for cracks/clogs, replace if necessary. 2. Inspect the check valves for damage, replace if necessary. 3. Inspect springs for damage, replace if necessary. 4. Inspect cover seal and diaphragm, replace if damaged. Cover Seal Diaphragm 90-828631R3 MARCH 1999 Page 3A-7...
FUEL PUMP Fuel Pump Reassembly 1. Assemble springs, diaphragm, and plunger onto pump body. Diaphragm Diaphragm Spring Pump Body Spring Plunger 2. Line up slots and compress assembly. 3. Insert pin into hole. Pump Body Slots 4. Rotate plunger 90 to offset slots. 53615 Slots Aligned Slots Offset...
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FUEL PUMP 5. Assemble diaphragm, seal, and cover, to pump body, secure with screws and nuts. NOTE: Seal installs in one direction only. Screws (4) Cover Cover Seal Diaphragm Pump Body Nuts (4) 6. Install a new O-ring onto the pump assembly. NOTE: Always install a new O-ring.
CARBURETOR Specifications Idle rpm (Out Of Gear) 45 hp 25 rpm 40/50 hp 25 rpm Idle RPM (In Forward Gear) 45 hp 25 rpm 40/50 hp 25 rpm CARBURETOR Wide Open Throttle rpm (WOT) Range 5500–6000 Main Jet Size 40/45 hp...
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CARBURETOR Carburetor Linkage TORQUE REF. REF. QTY. DESCRIPTION lb-in. lb-ft DIAPHRAGM JOINT SCREW Drive Tight PIPE PIPE (Qty. of 2 with carb with adjustable pilot screw/ Qty. of 1 with carb with non-adjustable pilot screw) PIPE PIPE CHOKE ROD JOINT WASHER CHOKE ROD CHOKE ROD...
CARBURETOR Intake Page 3B-10 90-828631R3 MARCH 1999...
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CARBURETOR Intake TORQUE REF. REF. QTY. DESCRIPTION lb-in. lb-ft SCREW O RING INSULATOR PLUG JOINT–carburetor DOWEL PIN O RING O RING O RING GROMMET STA–STRAP BREATHER PIPE CLAMP COLLAR SCREW SCREW COLLAR INTAKE SILENCER ASSEMBLY CABLE TIE PLUG CLAMP HOSE CONNECTOR HOSE HOSE...
CARBURETOR Carburetor Adjustments Carburetor Synchronization-Static Adjustment NOTE: This static adjustment is necessary if the throttle stop screws were loosened or tam- pered with. The initial static setting is preparation for the Carburetor Synchronization-dy- namic adjustment (Section 2C). 1. Remove the carburetors as a unit. 2.
CARBURETOR Idle Mixture Screw Adjustment-Static Adjustment NOTE: Idle mixture screw adjustment is required when carburetor has been overhauled. NOTE: Screw Adjuster (91-809906A1) is required to adjust the idle mixture screws on 45 hp models. NOTE: The idle mixture screw is: Adjustable: -All model years for the 45 hp version.
CARBURETOR Choke Cam Angle Adjustment NOTE: Choke cam angle adjustment is required when #4 carburetor has been replaced or overhauled. 1. Measure gap “a” and refer to the thermal gap graph, if out of specification adjust. 2. Adjustment steps: a. Loosen cam angle adjustment screw. b.
CARBURETOR Fast Idle Adjustment NOTE: Fast idle adjustment is required when fast idle exceeds 1500 rpm or engine stalls during a cold start. 1. Remove the link rods (a & b) and loosen fast idle screw (c). 2. Loosen idle stop screw (d) until the screw is free from the lever. 3.
CARBURETOR Unloader Adjustment NOTE: Unloader adjustment is required when the unloader adjustment screw has been loosened. 1. Disconnect the choke actuator rod (a). 2. Loosen the unloader adjustment screw (c). 3. Close the choke valve fully. NOTE: Check for a fully closed choke valve by depressing the #4 carburetor choke lever, then check the #1 carburetor choke lever to see that it is touching the stopper.
CARBURETOR Choke Shutter Closing Adjustment 1. Measure gap “a” and refer to the thermal gap graph below, if out of specification adjust. 2. Adjust gap by tightening/loosening the choke valve closing screw (b) to obtain the speci- fied gap found on the graph. Choke Shutter Closing Screw THERMAL GAP GRAPH Temp.
CARBURETOR Carburetor Unit Removal 1. Remove fuel line sta-straps. 2. Disconnect fuel lines and breather hose. 3. Disconnect solenoid and plunger leads. 28379 Sta-Straps (3) Breather Hose Fuel Lines (2) Solenoid Leads (Blue, Black) Plunger Leads (Green/White, Black) 4. Remove bolts and collars. 28379 Bolt w/Washer-M6x30 mm (2) Collar (2)
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CARBURETOR 5. Remove carburetor unit from intake manifold. 53679 6. Remove dowel pins. 7. Remove insulator from carburetor by prying near the plugs. 53679 Dowel Pin (2) Insulator Plug (2) 90-828631R3 MARCH 1999 Page 3B-19...
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CARBURETOR NOTE: Do not loosen or remove screw a, b, c, or d. Fine adjustments will be required if these screws are tampered with. 28379 Screw “a” Screw “b” Screw “c” Screw “d” Page 3B-20 90-828631R3 MARCH 1999...
CARBURETOR Carburetor Link Removal 1. Unsnap links from retainer clips. 28379 Upper Choke Link-“C” Link Lower Choke Link-“J” Link Auto Choke Link-“Z” Link Unloader Link-Small “J” Link Throttle Link Joint Plate Retainer Clips 90-828631R3 MARCH 1999 Page 3B-21...
CARBURETOR 5. Remove idle mixture screw. NOTE: 45 hp Models – Screw Adjuster (91-809906A1) is required to remove idle mixture screw. 53674 Idle Mixture Spring Idle Mixture Screw Plug Inspection CAUTION Do not use steel wire for cleaning the jets as this may enlarge the jet diameters and seriously affect performance.
CARBURETOR 4. Inspect main jet, pilot jet and main nozzle. Clean if they are contaminated. 53672 5. Inspect needle valve, replace if end is worn or grooved. 28375 Carburetor Assembly NOTE: Note different carburetor design from old style to new style for top carburetor (#1). New style does not have breather port.
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CARBURETOR 1. Install idle mixture screw. Lightly seat idle mixture screw and then back out 2.5 turns. NOTE: 45 hp Models – Use Screw Adjuster (91-809906A1) to install idle mixture screw. 53674 Idle Mixture Spring Idle Mixture Screw Plug 2. Install nozzle and jets. 53676 Plug Nozzle...
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CARBURETOR NOTE: Measure float height with carb. scale, replace float if height is not within specification [0.39 " 0.02 in. (10.0 " 0.5mm )] . Take measurements at the mid-line of the float opposite its pivot side. After installing, check for smooth movement of the float. 28380 4.
CARBURETOR Installation 1. Secure pump link with retainer, install screws, and connect delivery hoses. 53681 Delivery Hoses (4) Screw (3) Retainer Breather Hose NOTE: On older models with breather port located on the top carburetor (#1), route breather hose through bracket flange. If replacing top carburetor with new carburetor, breather hose is not needed.
CARBURETOR Carburetor Link Installation 1. Snap links onto retainer clips. Apply a light oil to link balls. 28378 4 Cycle Outboard Oil (92-828000A1) Upper Choke Link-“C” Link Lower Choke Link-“J” Link Auto Choke Link-“Z” Link Unloader Link-Small “J” Link Throttle Link Joint Plate Retainer Clips 90-828631R3 MARCH 1999...
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EMISSIONS FUEL SYSTEM Section 3C – Emissions Table of Contents Exhaust Emissions Standards ....3C-2 Stratified Vs Homogenized Charge ..3C-4 What Are Emissions? .
EMISSIONS Exhaust Emissions Standards Through the Environmental Protection Agency (EPA), the federal government has estab- lished exhaust emissions standards for all new marine engines sold in the U.S. What Are Emissions? Emissions are what comes out of the exhaust system in the exhaust gas when the engine is running.
EMISSIONS Stoichiometric (14.7:1) Air/Fuel Ratio In the search to control pollutants and reduce exhaust emissions, engineers have discov- ered that they can be reduced effectively if a gasoline engine operates at an air/fuel ratio of 14.7:1. The technical term for this ideal ratio is stoichiometric. An air/fuel ratio of 14.7:1 provides the best control of all three elements in the exhaust under almost all conditions.
EMISSIONS STRATIFIED VS HOMOGENIZED CHARGE DFI engines use a stratified charge inside the combustion chamber to aid in reducing emis- sions. All other models use a homogenized charge. The difference between the two is: Homogenized Charge A homogenized charge has the air/fuel particles mixed evenly throughout the cylinder. This mixing occurs inside the carburetor venturi, reed blocks and crankcase.
EMISSIONS Stratified Charge A stratified charge engine only pulls air through the transfer system. The fuel required for combustion is forced into the cylinder through an injector placed in the top of the cylinder (head). The injector sprays an air/fuel mixture in the form of a bubble into the cylinder. Sur- rounding this bubble is air supplied by the transfer system.
EMISSIONS Emissions Information Manufacturer’s Responsibility: Beginning with 1998 model year engines, manufacturers of all marine propulsion engines must determine the exhaust emission levels for each engine horsepower family and certify these engines with the United States Environmental Protection Agency (EPA). A certifica- tion decal/emissions control information label, showing emission levels and engine specifi- cations directly related to emissions, must be placed on each engine at the time of manufac- ture.
EMISSIONS EPA Emission Regulations: All new 1998 and later outboards manufactured by Mercury Marine are certified to the United States Environmental Protection Agency as conforming to the requirements of the regulations for the control of air pollution from new outboard motors. This certification is con- tingent on certain adjustments being set to factory standards.
Recommended spark plug for best engine performance Valve Clearance (Four Stroke engines only) Engine Horsepower rating Month of production (Boxing month will punched) FEL: Represents (Mercury Marine) statement of the maximum emissions output for the engine family Family example W M9X M. 747 2 2 0...
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CYLINDER HEAD Cylinder Head 10 11 Loctite PST Pipe Sealant (92-809822) 2-4-C w/Teflon (92-825407A12) 4-Stroke Outboard Oil (92-828000A12) Page 4A-4 90-828631R3 MARCH 1999...
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CYLINDER HEAD Cylinder Head TORQUE REF. REF. QTY. DESCRIPTION lb-in. lb-ft – CYLINDER HEAD ASSEMBLY CYLINDER HEAD SCREW WASHER GUIDE CIRCLIP BOLT Drive Tight GASKET ANODE GROMMET COVER SCREW (M6 x 20) Drive Tight BOLT SCREW (M4 x 10) Drive Tight COVER O RING COVER...
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CYLINDER HEAD Camshaft/Oil Pump 2-4-C With Teflon (92-825407A12) 4-Stroke Outboard Oil (92-828000A12) Page 4A-6 90-828631R3 MARCH 1999...
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SPRING TENSIONER ASSEMBLY SCREW (M8 x 20) 18.5 SCREW SPACER LOAD RING WASHER GEAR–Drive BELT SCREW (M8 x 40 x 1.25) WASHER GEAR–Driven OIL SEAL DOWEL PIN CAMSHAFT OIL PUMP ASSEMBLY O RING O RING O RING SCREW (M6 x 40) 68.0...
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CYLINDER HEAD Intake/Exhaust Valves 4-Stroke Outboard Oil (92-828000A12) Page 4A-8 90-828631R3 MARCH 1999...
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CYLINDER HEAD Intake/Exhaust Valves TORQUE REF. REF. QTY. DESCRIPTION lb-in. lb-ft EXHAUST VALVE INTAKE VALVE SEAT–Valve Spring SEAL–Valve Stem VALVE SPRING–Outer RETAINER–Valve Spring ROCKER ARM SCREW 13.5 ROCKER SHAFT PLATE PLATE SPRING SCREW (M8 x 30)160 13.3 PLUG 90-828631R3 MARCH 1999 Page 4A-9...
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CYLINDER HEAD Valve Clearance Adjustment NOTE: Valves should be adjusted when engine is cold. WARNING Engine could possibly start when turning flywheel during adjustment. To prevent this type of accidental engine starting and possible serious injury, always remove spark plug leads from spark plugs. Cylinder Head Cover Removal 1.
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CYLINDER HEAD Adjusting Valves NO. 1 AND NO. 2 INTAKE VALVES NO. 1 AND NO. 3 EXHAUST VALVES 1. Disconnect spark plug leads. 2. Turn the driven gear and align the “1” mark on the gear with the cylinder head mark “n ”. 3.
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CYLINDER HEAD Adjusting Valves NO. 3 AND NO. 4 INTAKE VALVES NO. 2 AND NO. 4 EXHAUST VALVES 1. Turn the driven gear and align the “4” mark on the gear with the cylinder head mark “n ”. 2. Adjust the valve clearance for No. 3 and No. 4 intake valves and No. 2 and No. 4 exhaust valves.
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CYLINDER HEAD Cylinder Head Cover Installation 1. Reinstall the cylinder head cover. Tighten bolts to the specified torque. 53734 Retainer Mounting Bolts (7) Cylinder Head Cover Bolt Torque 70 lb-in. (8 Nm) 2. Reinstall the fuel pump. Tighten bolts to the specified torque. 3.
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CYLINDER HEAD Timing Belt Inspection Replace timing belt if any of the following conditions are found: Cracks in the back of the belt or in the base of the belt teeth. Excessive wear at the roots of the cogs. Rubber portion swollen by oil. Belt surfaces roughened.
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CYLINDER HEAD 3. Remove flywheel using puller (91-83164M). 30025 Flywheel Puller (91-83164M) 4. Remove the stator. 53745 Stator Stator Mounting Bolts 90-828631R3 MARCH 1999 Page 4A-15...
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CYLINDER HEAD 5. Remove the trigger base. 30027 Trigger Base 6. Turn the driven gear and align the “1” mark with the cylinder head mark “n ”. 30033 7. Loosen belt tensioner fastening bolt to release the tension. 8. Remove the timing belt. 30033 Belt Tensioner Fastening Bolt Timing Belt...
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CYLINDER HEAD Timing Belt Installation Timing Belt Installation Notes: Protect the timing belt from water and oil. Use care not to scratch the belt. Do not use any metal device to help stretch the belt onto the driven gear. 1. Align drive gear mark with cylinder mark. 30033 Drive Gear Mark Cylinder Mark...
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CYLINDER HEAD 3. Install timing belt as follows: Align both gears with their alignment marks (Steps 1 and 2). IMPORTANT: Make sure the Part Number on the belt is upright, not inverted. Install the timing belt around the gears as shown. NOTE: The spring loaded belt tensioner will automatically apply the correct tension against the belt.
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CYLINDER HEAD 5. Reinstall stator with three bolts. 53745 Stator Mounting Bolts (3) Apply Loctite 222 to Threads Stator Bolt Torque 75 lb-in. (8.5 Nm) 6. Place flywheel key into slot. 7. Install flywheel. 8. Hold flywheel using flywheel holder (91-83163M). Apply oil to threads on crankshaft. Tighten nut to the specified torque.
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CYLINDER HEAD FLYWHEEL WITH LOAD RING & SPACER 53278 Flywheel Key Washer Apply Oil to Threads Spacer Load Ring NOTE: Load Ring is for one time use and must be replaced if flywheel is removed. Flywheel Nut Torque 116 lb-ft (157 Nm) Page 4A-20 90-828631R3 MARCH 1999...
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CYLINDER HEAD Cylinder Head Disassembly Cylinder Head Cover Removal 1. Disconnect the breather hose and vent hose from the cylinder head cover. IMPORTANT: The hose fittings on the fuel pump can break if you try twisting or pull- ing off the hoses. Remove hoses by slowly prying off the hoses using a small screw- driver.
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CYLINDER HEAD Cylinder Head Removal 1. Remove timing belt from driven gear. 2. Remove spark plugs leads from spark plugs. 3. Remove the throttle and shift levers from side of cylinder head. 4. Remove the cylinder head mounting bolts. 5. Separate the cylinder head from the block. 53727 Center Bolts (10) Flange Bolts (5)
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CYLINDER HEAD Rocker Arm Assembly Removal 1. Remove five bolts and the rocker arm shaft. 53740 Rocker Arm Shaft Bolts (5) Oil Pump Removal 1. Remove four bolts and pull out the oil pump assembly. 53732 Oil Pump Assembly Bolts (4) 90-828631R3 MARCH 1999 Page 4A-23...
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CYLINDER HEAD Camshaft Removal 1. Hold driven gear using tool (91-83163M) and remove bolt and flat washer. Remove driv- en gear. 2. Remove camshaft retaining bolt. Slide camshaft out of cylinder head. NOTE: The cam can also be removed from the top without removing the cylinder head from engine.
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CYLINDER HEAD Valve Removal VALVE COMPONENTS Valve Spring Seat Valve Seal Valve Spring Spring Retainer Valve Keepers REMOVING VALVES 1. Anytime a valve is removed, replace the valve seal. 2. Remove valves as shown. 53735 Use Spring Compressor Tool (91-809494A1) to Compress the Springs for Removal Compress the Spring and Remove the Valve Keepers 90-828631R3 MARCH 1999...
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CYLINDER HEAD Anode Removal 1. Check condition of the anodes. Replace, if anodes show sign of deterioration. NOTE: If anodes are not deteriorated, wire brush corrosion off before installation. 2-4-C w/Teflon (92-850736A1) Anode Cover Bolt Rubber Seal Anode Oil Pump Disassembly 1.
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CYLINDER HEAD Cleaning and Inspection Oil Pump 1. Check oil pump components for pitting, scratches, and for the following measurements. Replace oil pump if worn or out of specification. 2. Using a feeler gauge, measure the following oil pump clearances: between outer rotor and pump housing (a) between the inner rotor and outer rotor (b) between the outer rotor and pump housing (c)
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CYLINDER HEAD Camshaft 1. Inspect the camshaft for pitting, heat discoloration, scratches and for the following mea- surements. Replace camshaft if worn or not within specification. 2. Measure the cam lobe length (a) and width (b). 55805 Cam Lobe Specifications Intake 1.216 - 1.220 in.
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CYLINDER HEAD Cylinder Head 1. Inspect the cylinder head for the following conditions: Mineral deposits/corrosion in water passage ways. Carbon Deposits In Combustion Chamber (use round scraper to clean away deposits). Be careful not to scratch or remove material. 2. Inspect cylinder head for warpage. Replace cylinder head If out of specification. Cylinder Head Warpage Limit 0.004 in.
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CYLINDER HEAD Valve Guide Replacement 1. Heat the cylinder head in an oven to 390 F (200 C). This will help to ease guide removal and installation and to maintain correct interference fit. 2. Remove the valve guide using a valve guide remover. 55806 Valve Guide Remover (91-809495A1) 3.
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CYLINDER HEAD Valves 1. Clean the carbon deposits from the valve. Discard any cracked, warped, or burned valves. 2. Measure the valve stem to check for wear. Replace valves if not in specification. 55810 Valve Stem Diameter “a” Intake Valve 0.2156 - 0.2161 in.
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CYLINDER HEAD Valve Springs Check free length limit of each spring. Replace valve springs if not in specification. 55846 Valve Spring Free Length 1.569 - 1.491 in. (39.85 – 37.85 mm) Check each spring on a flat surface using a square. Rotate spring and check space between the top coil and square.
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CYLINDER HEAD Valve Seat Reconditioning Clean the carbon deposits from the combustion chambers and valve seats and check for pitting. Several different types of equipment are available for reseating valve seats. Follow the equipment manufacturer’s instructions. Measure valve seat width (a). Resurface the valve seat If not in specification. 55799 Valve Seat Width Specification “a”...
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CYLINDER HEAD Valve Refacing Steps Condition: The valve seat is centered on valve face but it is too wide. 55799 Valve Seat Cutter Set Desired Results 15 Cutter To reduce valve seat width Li htl Lightly 60 Cutter Condition: The valve seat is in the middle of the valve face but it is too narrow. 55800 Valve Seat Cutter Set Desired Results...
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CYLINDER HEAD Condition: Valve seat is too narrow and is located near the bottom edge of the valve face. 55802 Valve Seat Cutter Set Desired Results 60 Cutter, First To center the seat and to in- crease its Width crease its Width 45 Cutter Cylinder Head Reassembly Valve Installation...
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CYLINDER HEAD INSTALLING VALVES 1. Always use new valve seals. 2. Apply engine oil to the valves and valve seats. 3. Install valves as shown. 91-809494A1 53735 End of the Valve Spring with the Pre-Compressed Coils gets Installed Towards the Cylinder Head Use Spring Compressor Tool to Compress the Springs for Installation Compress the Spring and Retainer and Install the Valve Keepers Around the Valve Stem.
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CYLINDER HEAD Camshaft Oil Seal Installation 1. If removed, install Oil Seal. Position seal so part number side is facing outward. Press seal in until it makes contact with the inside flat surface. NOTE: Seal must be properly seated before it is secured in place with a bead of Loctite 499 Super Bonder.
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CYLINDER HEAD Camshaft Installation 1. Apply engine oil to the main journals (5 places) on the camshaft. 2. Slide camshaft into cylinder head (threaded end towards driven gear). 3. Install camshaft retaining bolt. Tighten bolt to the specified torque. 4. Place driven gear on camshaft so alignment pin is in hole. Hold gear with tool (91-83163M) and fasten with washer and bolt.
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CYLINDER HEAD Oil Pump Assembly 1. Reassemble the oil pump assembly. 2. Lubricate the outer and inner rotors thoroughly with engine oil. 53741 Cover Seal Outer Rotor Inner Rotor Shaft Cross Pin 3. Fasten cover with two screws. Apply Loctite 222 to threads. Tighten screws to the speci- fied torque.
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3. Align oil pump shaft with the camshaft and install the oil pump. 4. Fasten with 4 bolts. Tighten bolts to the specified torque. 53738 Oil Pump Assembly Align Slot with Camshaft Projection Bolt (4) Oil Pump Mounting Bolt Torque 68 lb-in. (7.6 Nm) Page 4A-40 90-828631R3 MARCH 1999...
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CYLINDER HEAD Rocker Arm Shaft Assembly 1. Apply engine oil to the rocker shaft and arms. 2. Locate the end of the rocker shaft that gets installed towards driven gear (oil holes will line-up with the mating oil holes in the cylinder head). 3.
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CYLINDER HEAD Cylinder Head Gasket 1. Install cylinder head gasket and dowel pins. Dowel Pin (2) Gasket Flange Seals (4) Cylinder Head Installation 1. Apply engine oil to the threads of each bolt and seat surface. 2. Fasten cylinder head with bolts shown. 53727 Center Bolts (10) Cylinder Head Flange Bolts (5)
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CYLINDER HEAD 3. Torque center bolts in sequence and in two steps, than torque the Cylinder Head and carburetor flange bolts. 53740 Cylinder Head Bolt Torque Center Bolts Qty. 10 (Larger Dia. M9) 1st: 17 lb-ft (23 Nm) 2nd: 34.7 lb-ft (47 Nm) Cyl.
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CYLINDER HEAD Cylinder Head Cover Installation 1. Install cover seal into groove. 2. If removed, reinstall diaphragm. Baffle Plate Screw (4) Cover Seal Diaphragm Bolt (2) 3. Install cylinder head cover. Tighten bolts to the specified torque. 53734 Retainer Mounting Bolts (7) Cylinder Head Cover Bolt Torque 70 lb-in.
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CYLINDER HEAD 4. Reinstall the fuel pump. Tighten bolts to the specified torque. 5. Reconnect hoses. Use sta-straps to fasten all hose connections. 6. Reconnect the throttle and shift levers. 53726 Breather Hose Top Fuel Hose Vent Hose Throttle and Shift Levers Sta-Straps Fuel Pump Mounting Bolt Torque 75 lb-in.
CYLINDER BLOCK/CRANKCASE Powerhead Removal WARNING Engine could possibly start when turning flywheel during removal and installation. To prevent this type of accidental engine starting and possible serious injury, always remove spark plug leads from spark plugs. 1. Remove the bottom cowls. 2.
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CYLINDER BLOCK/CRANKCASE 5. Remove powerhead mounting bolts. 53868 Powerhead Mounting Bolts (4 Each Side) 6. Lift powerhead from drive shaft housing. Hoist Page 4B-10 90-828631R3 MARCH 1999...
CYLINDER BLOCK/CRANKCASE Removing Powerhead Components 1. Place powerhead on Powerhead Stand. 91-827001A1 91-812549 Powerhead Stand (91-827001A1-Non-Bigfoot) (91-812549-Bigfoot) 2. Remove flywheel, stator, trigger base, and timing belt. Refer to Section 4 Part A. 30033 90-828631R3 MARCH 1999 Page 4B-11...
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CYLINDER BLOCK/CRANKCASE 3. Remove 8 flange bolts and 2 side mounting bolts and lift carburetor assembly from pow- erhead. Disconnect hoses and wiring as necessary. IMPORTANT: The hose fittings on the fuel pump can break if you try twisting or pull- ing off the hoses.
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CYLINDER BLOCK/CRANKCASE 4. Remove the control cable anchor bracket. 5. Remove shift and throttle lever. 53869 Control Cable Anchor Bracket Shift and Throttle Lever 6. Remove cylinder head. Refer to Section 4 Part A. 53740 90-828631R3 MARCH 1999 Page 4B-13...
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CYLINDER BLOCK/CRANKCASE 7. Remove four bolt securing starter bracket. 8. Cut sta-straps and lift starter bracket, electrical components and wiring harness from engine. Disconnect wiring as necessary. 53866 Starter Bracket Mounting Bolts (4) Page 4B-14 90-828631R3 MARCH 1999...
CYLINDER BLOCK/CRANKCASE Cylinder Block Disassembly 1. Hold crankshaft from turning using Powerhead Stand (91-827001A1). Remove nut using 1-5/8 in. Socket Tool (91-809646A1). 2. Remove the drive gear components. CRANKSHAFT WITH NUT 53742 Drive Gear Nut Washer (2) Drive Gear 1-5/8 in. Socket Tool (91-809646A1) Use for Removing Drive Gear Nut CRANKSHAFT WITHOUT NUT Washer, Lower Woodruff Key...
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CYLINDER BLOCK/CRANKCASE 6. Insert a screwdriver at the pry points between the crankcase cover and block to sepa- rate. 53744 7. Use a 5/16 in. 12 point socket and remove connecting rod bolts. 8. Remove carbon ridge from the cylinder bore using a burr knife. Push out the pistons. Keep each piston, connecting rod, and cap together as an assembly.
CYLINDER BLOCK/CRANKCASE 9. Remove crankshaft from block. Main Bearings – Do Not Interchange. Reinstall in Original Locations Inspection Cylinder Bore MEASURING CYLINDER BORE 1. Measure the cylinder bore diameter “d” at three locations in both X and Y axis. 2. If the cylinder bore is beyond the standard limits listed in the tables below, it will be nec- essary to re-bore the cylinder to accept the oversize piston.
CYLINDER BLOCK/CRANKCASE Piston MEASURING PISTON 1. Measure the piston at a point 0.2 in. (5.0 mm) from the bottom. 55838 Piston Diameter 0.2 in. (5.0 mm) Piston Diameter “a” Diameter (Standard) 2.4783 - 2.4789 in. (62.950 - 62.965 mm) (Oversize) 0.020 in. (0.50 mm) 2.4983 - 2.4989 in.
CYLINDER BLOCK/CRANKCASE Piston Pin 1. Measure piston pin diameter. Replace piston pin if out of specification. 55839 Piston Pin Diameter 0.6285 - 0.6287 in. (15.965 - 15.970 mm) 1. Place the piston pin into the connecting rod and check for free play. There should be no noticeable free play.
CYLINDER BLOCK/CRANKCASE Piston Rings PISTON RING SIDE CLEARANCE 1. Measure piston ring side clearance. Replace piston and/or piston rings if out of specifi- cation. 55842 Piston Ring Side Clearance 0.002 - 0.003 in. (0.04 - 0.08 mm) 0.001 - 0.003 in. (0.03 - 0.08 mm) PISTON RING END GAP CLEARANCE 1.
CYLINDER BLOCK/CRANKCASE Crankshaft 1. Thoroughly clean crankshaft and inspect bearing surfaces. Replace crankshaft if bear- ing surfaces are pitted, scored, or discolored. 2. Measure Run-out. Replace crankshaft if out of specification. Crankshaft Run-out 0.0012 in. (0.03 mm) Checking Main Bearing Clearance IMPORTANT: Do not interchange the main bearings.
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CYLINDER BLOCK/CRANKCASE 5. Place a piece of plastigauge onto each crankshaft bearing surface. 53812 Plastigauge 6. Install crankcase cover. Apply oil to the cover bolts and torque cover bolts in sequence and in two steps. 53743 Crankcase Cover Bolt Torque Center Bolts Qty.
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CYLINDER BLOCK/CRANKCASE 7. Remove the crankcase cover. Measure the compressed plastigauge to check the main bearing clearance. Replace bearings if clearance is not in specification. 53751 Main Bearing Clearance 0.0005 - 0.0017 in. (0.012 - 0.044 mm) 8. If replacement of the main bearings is required, refer to Main Bearing Selection and Installation in Cylinder Block Reassembly.
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CYLINDER BLOCK/CRANKCASE 3. Install the connecting rod to the respective journal. Tighten connecting rod bolts in se- quence and in two steps to the specified torque. 53814 Connecting Rod Bolts Connecting Rod Bolt Torque 1st: 53 lb-in. (6 Nm) 2nd: 150 lb-in. (17 Nm) 4.
CYLINDER BLOCK/CRANKCASE Thermostat 1. Measure the lift of the thermostat at the operating water temperature listed. 55843 Water Temperature Valve Lift 136 -143 F (58 - 62 C) 0 in. (0 mm) Above 158 F (70 C) Minimum 0.12 in. (3 mm) Oil Pressure Switch 1.
CYLINDER BLOCK/CRANKCASE Cylinder Block Reassembly Selecting New Main Bearings 1. Locate the main bearing code letters on the cylinder block. 2. Refer to the following reference chart to select the correct main bearings. 3. Use the color coded main bearings that match the main bearing code letter. Main Bearing Code Main Bearing Color Code Letter...
CYLINDER BLOCK/CRANKCASE Main Bearing Installation IMPORTANT: Do not interchange used main bearings. Reinstall in their original posi- tion. 1. Check clearance of each bearing, following procedure in Cleaning and Inspection. 2. Clean all the oil from the main bearing surfaces on the cylinder block and crankcase cover.
CYLINDER BLOCK/CRANKCASE Selecting New Connecting Rod Bearings 1. Locate the connecting rod bearing code letter that is scribed on the side of the connect- ing rod. 2. Refer to the following reference chart to select the correct connecting rod bearings. 3.
CYLINDER BLOCK/CRANKCASE Connecting Rod Installation 1. Lubricate the piston pin with oil and assemble the piston to the connecting rod. Always use new circlips. IMPORTANT: Install side of connecting rod marked with a “Y” towards “UP” on pis- ton. Circlip Piston Pin Side Marked “Y”...
CYLINDER BLOCK/CRANKCASE 2. Install the second and top compression rings (“T” side up). Spread rings just enough to slip over piston. 53818 Top Compression Ring ( “T” Side Up) Second Compression Ring ( “T” Side Up) Install Side of Ring Stamped “T” Towards Top of Piston Piston Installation 1.
CYLINDER BLOCK/CRANKCASE 2. Lubricate pistons, rings, and cylinder walls with engine oil. 3. Install each piston in its respective cylinder. NOTE: Install used pistons into same cylinder from which they were removed. 4. Use Piston Ring Compressor (FT2997) to compress rings. 5.
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CYLINDER BLOCK/CRANKCASE 5. Apply oil to the connecting rod bolts. Tighten bolts in sequence and in two steps to the specified torque. 53823 Apply Oil to Bolt Threads Connecting Rod Bolt Torque 1st: 53 lb-in. (6 Nm) 2nd: 150 lb-in. (17 Nm) 6.
CYLINDER BLOCK/CRANKCASE Crankcase Cover Installation 1. Clean off all oil from the contacting surfaces of the crankcase cover and cylinder block. IMPORTANT: Make sure the contacting surface of the crankcase cover and cylinder block are clean before applying gasket sealant. 2.
CYLINDER BLOCK/CRANKCASE Exhaust Cover Installation 1. Install oil filter. 2. Install exhaust cover along with the thermostat and thermostat cover. Use new gaskets. 3. Tighten bolts in sequence and in two steps to the specified torque. 4. Install the oil pressure and temperature switch. 53746 Exhaust Cover Gasket...
CYLINDER BLOCK/CRANKCASE Drive Gear Installation CRANKSHAFT WITH NUT 1. Install the drive gear components. 2. Hold crankshaft from turning using Powerhead Stand (91-827001A1). Tighten nut to the specified torque using 1-5/8 in. Socket Tool. 53742 Drive Gear Nut Washer (2) Drive Gear Drive Key Insert Projections (3) on the Drive Gear into the Holes in the washers...
CYLINDER BLOCK/CRANKCASE CRANKSHAFT WITHOUT NUT 4-Stroke Outboard Oil (92-828000A12) NOTE: Load Ring is for one time use and must be replaced if flywheel is removed. Washer, Lower Woodruff Key Drive Gear Washer, Upper Load Ring Spacer Insert Projections (3) on the Drive Gear into washer holes Installing Powerhead Components 1.
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CYLINDER BLOCK/CRANKCASE 2. Install Timing belt. Refer to Section 4 Part A. 30033 3. Install starter bracket with 4 bolts. Tighten bolts to the specified torque. 53866 Starter Bracket Mounting Bolts (4) Starter Bracket Mounting Bolt Torque 210 lb–in. (23.7 Nm) Page 4B-38 90-828631R3 MARCH 1999...
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CYLINDER BLOCK/CRANKCASE 4. Install ignition coils and reattach engine wiring harness. 30028 Top Ignition Coil Bottom Ignition Coil Fasten (and Ground) Coil Ground Leads with Bolt Sta-Strap Ignition Coil Mounting Bolt Torque 62 lb-in. (7 Nm) 5. Reinstall trigger base with four bolts. 30027 Trigger Base Mounting Bolts (4)
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7. Place flywheel key into slot. 8. Install flywheel. 9. Apply oil to threads on crankshaft and tighten nut to the specified torque. Flywheel Key Washer Apply Oil to Threads Flywheel Nut Torque 116 lb-ft (157 Nm) Page 4B-40 90-828631R3 MARCH 1999...
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CYLINDER BLOCK/CRANKCASE 10. Install shift and throttle lever. 11. Install control cable anchor bracket. 53869 Cable Anchor Bracket Shift and Throttle Lever Bushing Bolt (1) Bolt and Bushing (2) Shift and Throttle Lever Mounting Bolt Torque 100 lb-in. (11.3 Nm) Cable Anchor Bracket Mounting Bolt Torque 75 lb-in.
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CYLINDER BLOCK/CRANKCASE 12. Reinstall carburetor assembly with 8 flange bolts and 2 side mounting bolts. Tighten bolts to the specified torque. Carburetor Assembly O-Ring Flange Seals (4) Flange Bolts (8) Side Mounting Bolts (2) Collar (2) Flange Bolt Torque 50 lb-in. (5.7 Nm) Side Bolt Torque 75 lb-in.
CYLINDER BLOCK/CRANKCASE 13. Reconnect hoses. Use sta-straps to fasten all hose connections. 53726 Breather Hose Fuel Hose (2) Remote Fuel Hose Sta-Straps Powerhead Installation 1. Install powerhead and new gasket with 8 bolts. Tighten bolts to the specified torque. 53868 Powerhead Mounting Bolts (4 Each Side) Gasket Powerhead Mounting Bolt Torque...
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CYLINDER BLOCK/CRANKCASE 2. Reconnect the vent hose. Use sta-strap to fasten hose connections. 53726 Vent Hose 3. Engage the vertical shift shaft. 4. Reconnect the power trim harness wires. 5. Position the trim wiring harness away from the moving horizontal shift shaft. Fasten har- ness to mounting boss with sta-strap as shown.
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Specifications Pump Type Trochoid Engine Oil Pressure (Warm Engine) @ 3000 rpm 30-40 psi (207-278 kPa) Engine Oil Pan Capacity Either 3 Qts. or 3 Liters Oil Pump: Outer Rotor to Housing “a” 0.001 - 0.006 in. (0.03 - 0.15 mm) Inner Rotor to Outer Rotor “b”...
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LUBRICATION Oil Pump Removal 1. Refer to section 4A for Cylinder Head Removal. 2. Remove oil pump bolts, separate oil pump from cylinder head. Bolts (4) M6x35 Oil Pump Disassembly 1. Heat screws to loosen Loctite sealant. Remove screws. Screw (2) Heat Screws to Loosen Loctite Sealant Page 4C-2 90-828631R3 MARCH 1999...
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LUBRICATION 2. Disassemble Oil Pump. Cover Seal Outer Rotor Inner Rotor Shaft Cross Pin Cleaning and Inspection Oil Pump 1. Check oil pump components for pitting, scratches, and for the following measurements. Replace oil pump if worn or out of specification. 2.
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LUBRICATION Oil Pump Assembly 1. Reassemble the oil pump assembly. 2. Lubricate the outer and inner rotors thoroughly with engine oil. Cover Seal Outer Rotor Inner Rotor Shaft Cross Pin 3. Fasten cover with two screws. Apply Loctite 222 to threads. Tighten screws to the speci- fied torque.
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LUBRICATION Oil Pump Installation 1. Place O-ring seals on the oil pump. Lubricate the O-rings with oil. 2. Prime the oil pump by pouring approximately 1 fl oz (30 ml) of engine oil into the oil pump body. O-Ring Seals Pour Approximately 1 fl oz (30 ml) of Engine Oil into the Oil Pump Body 3.
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POWER TRIM SCREW Drive Tight SCREW Drive Tight WASHER Drive Tight LINK TILT LEVER BUSHING NON POWER TRIM WASHER WAVE WASHER TILT KNOB SCREW (.375-16 x .62) 18.3 24.9 SCREW (M10 x 40) WASHER DECAL-Tilt Lock 90-828631R3 MARCH 1999 Page 5A-3...
CLAMP/SWIVEL BRACKETS & DRIVESHAFT HOUSING Swivel Bracket A = TORQUE NUT 120 LB-IN. (13.5 NM) AND THEN BACK OFF 1/4 TURN. 2-4-C w/Teflon (92-825407A12) Page 5A-4 90-828631R3 MARCH 1999...
CLAMP/SWIVEL BRACKETS & DRIVESHAFT HOUSING Co-Pilot Installation 1. Apply 2-4-C Marine Lubricant with Teflon to threads on the threaded rod. 2. Thread rod into swivel bracket to a height of 7/8 in. (22.2 mm). 7/8 in. (22.2 mm) 54275 2-4-C w/Teflon (92-850736A1) Threaded Rod 3.
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CLAMP/SWIVEL BRACKETS & DRIVESHAFT HOUSING 5. Install remaining co-pilot components. 54275 54276 Brake Disc (2) Swivel Head Plate Hex Shoulder Screw (2) Brake Plate Nylon Washer Co-Pilot Lever Lock Nut (Tighten Next Step) Page 5A-18 90-828631R3 MARCH 1999...
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CLAMP/SWIVEL BRACKETS & DRIVESHAFT HOUSING 6. Adjust the co-pilot steering friction as follows: Loosen the secondary steering friction screw. This screw can be used after the co-pilot lever has been adjusted to add steering friction on the tiller handle. Secondary Steering Friction Screw Set the co-pilot lever to the full friction (left side) position.
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POWER TRIM MID-SECTION Section 5B – Power Trim 1998 and Earlier Non-Bigfoot Table of Contents Special Tools ......5B-2 Disassembly .
POWER TRIM Power Trim NOTE: Lubricate all O-rings using Quicksilver Power Trim and Steering Fluid. If not available, use automotive (ATF) automatic transmission fluid. NOTE: It is recommended that all O-rings be replaced when servicing tilt system. Liquid Neoprene (92-25711--2) Page 5B-4 90-828631R3 MARCH 1999...
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POWER TRIM Power Trim TORQUE REF. REF. QTY. DESCRIPTION lb-in. lb-ft POWER TRIM ASSEMBLY – O RING KIT SHOCK ROD ASSEMBLY PILOT CHECK ASSEMBLY 13.5 TILT RELIEF VALVE ASSEMBLY 13.5 SUCTION SEAT ASSEMBLY 13.5 PUMP ASSEMBLY SPRING/DOWN RELIEF BALL SCREW (10-32 x 1-1/4 IN.) FILTER SEAL RING MOTOR ASSEMBLY...
POWER TRIM Theory Of Operation The Power Trim system consists of an electric motor, pressurized fluid reservoir, pump and trim cylinder. The remote control (or trim panel) is equipped with a switch that is used for trimming the outboard “up” and “down”, and for tilting the outboard for shallow water operation (at slow speed) or for “trailering”.
POWER TRIM The engine can be raised beyond the 20_ maximum trim angle for shallow water operation, etc., by keeping the engine rpm below 2000 rpm. If engine rpm increases above 2000 rpm, the thrust created by the propeller (if deep enough in the water) will cause the trim system to automatically lower the engine back to the 20_ maximum trim angle.
POWER TRIM Trim “In” Angle Adjustment WARNING Operating some boats with engine trimmed to the full “in” trim angle at planing speed will cause undesirable and/or unsafe steering conditions. Each boat must be water tested for handling characteristics after engine installation and after any trim adjustments.
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POWER TRIM Notes: 90-828631R3 MARCH 1999 Page 5B-9...
POWER TRIM Power Trim Flow Diagrams TRIM UP Reservoir and Feed Oil Oil Under Pressure Return Oil Up Pressure 2530 psi (min) Page 5B-10 90-828631R3 MARCH 1999...
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POWER TRIM Trim Up When the trim switch is activated in the up position, the electric motor (a) begins to rotate the oil pump gears (n), the oil pump draws a small amount of oil through the filter, up circuit pick-up and past the up circuit feed check ball (o).
POWER TRIM TILT UP Reservoir and Feed Oil Oil Under Pressure Return Oil Tilt Relief Pressure 500-600 psi Page 5B-12 90-828631R3 MARCH 1999...
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POWER TRIM Tilt Up In the up mode, as the trim rod (b) extends from the cylinder, the memory piston (e) clears or uncovers the pressure relief passage. Oil from the up cavity will enter this passage and open the tilt pressure relief valve (k). This valve lowers the amount of pressure available to lift the outboard motor.
POWER TRIM MAXIMUM TILT Reservoir and Feed Oil Oil Under Pressure Return Oil Tilt Relief Pressure 500-600 psi Page 5B-14 90-828631R3 MARCH 1999...
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POWER TRIM Maximum Tilt With the cylinder at maximum travel, and due to no ram movement, the pressure inside of the trim cylinder will increase to the pressure required to move the tilt relief actuator (i). The tilt relief actuator’s “pin” opens the tilt relief valve (k). Up pressure flows into the trim relief passage, and return back into the reservoir (t).
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POWER TRIM TRIM DOWN Reservoir and Feed Oil Oil Under Pressure Return Oil Down Relief 500-800 psi Page 5B-16 90-828631R3 MARCH 1999...
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POWER TRIM Trim Down When the trim switch is activated in the down position, the electric motor (a) will rotate the oil pump gears (n) in the opposite direction. With the oil pump gears rotating backwards, the flow of oil is reversed. Oil is drawn through the filter, past the up circuit feed check ball (m), into the down circuit oil pick-up and finally into the oil pump.
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POWER TRIM SHOCK FUNCTION UP Reservoir and Feed Oil Oil Under Pressure Return Oil 1550-1850 psi Page 5B-18 90-828631R3 MARCH 1999...
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POWER TRIM Shock Function Up Oil inside the down cavity is locked in a static position by the closed down circuit pressure operated valve (h), the manual release valve (j) and the tilt relief valve (k). If the outboard strikes an underwater object while in forward gear the trim rod (b) will try to rapidly extend from the cylinder , the pressure increases inside the trim cylinder down cavity and connect- ing passages.
POWER TRIM SHOCK FUNCTION RETURN Reservoir and Feed Oil Oil Under Pressure Return Oil Page 5B-20 90-828631R3 MARCH 1999...
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POWER TRIM Shock Function Return After the engine clears the under water object, the weight of the engine will increase the oil pressure between the memory piston (e) and shock piston (d) to the level required to open the shock return valve (v), inside the shock piston, allowing the oil to bleed back through the shock piston into the down cavity.
POWER TRIM MANUAL TILT Reservoir and Feed Oil Return Oil Page 5B-22 90-828631R3 MARCH 1999...
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POWER TRIM Manual Tilt To manually tilt the outboard engine, the owner will need to back out the manual release valve (j). With the valve backed out, the internal passages inside the manifold are connected together. These passages connect both the cylinder down and up cavities together, along with the reservoir (t), allowing the engine to be raised or lowered.
POWER TRIM Troubleshooting Support outboard with tilt lock pin when servicing power trim system. IMPORTANT: After debris or failed components have been found (during trouble- shooting procedure) it is recommended that unit be disassembled completely and ALL O-rings be replaced. Check ball valve components and castings must be cleaned using engine cleaner and compressed air or replaced prior to re-assembly.
POWER TRIM Hydraulic System Troubleshooting Flow Chart OUTBOARD WILL NOT HOLD TILTED POSITION DURING REVERSE AND/OR TRAILS OUT DURING HIGH SPEED DECELERATION Manual release Manual release valve and Inspect manual release valve valve and O-ring O-rings appear to be O.K. damaged Clean and reinstall manu- al release valve...
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POWER TRIM continued Remove suction seat as- sembly and inspect for debris and/or damage Suction seat assembly Debris and/or damage appears O.K. - Clean and identified reinstall suction seat as- sembly Replace suction seat Trim will not hold assembly Trim system holds reverse thrust reverse thrust:...
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POWER TRIM Hydraulic System Troubleshooting Flow Chart TRIM SYSTEM LEAKS DOWN WITH MANUAL RELEASE VALVE CLOSED Manual release Inspect manual release valve Manual release valve and O- valve and O-ring rings appear to be O.K. - Clean damaged and reinstall manual release valve Replace manual re- Trim...
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POWER TRIM continued Remove PO check valve assembly, inspect rings and seals for dam- Debris and/or damage PO check valve appears identified O.K. - Clean and reinstall PO check valve assembly Replace PO check valve assembly Trim system does Trim system leaks leak...
POWER TRIM Troubleshooting the Power Trim Electrical System BLU/WHT GRN/WHT BLU/WHT or PUR GRN/WHT or GRN RED/PUR – RED/PUR GRN/WHT BLU/WHT LT. GRN/WHT GRN/WHT 14 BLK LT. GRN/WHT LT. BLU/WHT LT.BLU/WHT BLUE 14 BLK LT. BLU/WHT Trim Switch (Remote Control Mounted) Trim Switch (Panel Mounted) Fuse Holder Remote Control...
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POWER TRIM Troubleshooting the Power Trim Electrical System Refer to wiring diagram on preceding page for location of wire connections. Problem Possible Cause Remedy Trim Switch “UP” is inopera- 1. Open wire between Wire Connection (1) 1. Check for a open connection or cut tive, but the Cowl Switch and Trim Switch.
POWER TRIM Power Trim System Removal 1. Tilt outboard to the full up position and support with tilt lock pin. 2. Disconnect the power trim wire harness and remove clamps. Tilt Lock Pin Power Trim Wire Harness Clamps 3. Remove the trilobe pin. 4.
POWER TRIM 6. Remove nuts and washers securing the lower pivot pin. Remove lower pivot pin. Retain the pivot pin bushings from the clamp brackets and trim unit. 7. Remove the trim unit. Disassembly Shock Rod Removal IMPORTANT: Power trim system is pressurized. Outboard must be in the full “UP” position (trim rod fully extended) prior to fill/drain plug, or manual release valve re- moval.
POWER TRIM 4. Secure power trim assembly in a soft jaw vise. 5. Unscrew end cap assembly from cylinder using spanner wrench 91-74951. 6. Remove shock rod assembly from cylinder. 91-74951 Shock Rod Disassembly NOTE: The only serviceable items on the shock rod assembly are the O-rings and wiper ring.
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POWER TRIM 3. Remove check ball components from shock rod piston. 4. Remove O-ring from shock rod piston. 51147 Spring (5) Seat (5) Ball (5) O-ring CAUTION When removing shock piston, spanner wrench must have 1/4 in. x 5/16 in. long pegs to avoid damage to shock piston.
POWER TRIM 8. Inspect check valve for debris; clean debris from check valve if found. If debris cannot be cleaned from check valve, replace shock piston as an assembly. 9. Clean shock and components with compressed air. 10. Remove inner O-ring from shock rod piston. 11.
POWER TRIM b. Blowing compressed air into manual release valve hole using air nozzle. WARNING Memory piston cup may be expelled at a high velocity when air pressure is applied. Failure to place cylinder as shown below could result in personal injury. NOTE: Point cylinder opening down and away.
POWER TRIM Oil Pump Removal 1. Remove oil filter and pump from manifold. IMPORTANT: DO NOT disassemble the oil pump. The pump is not serviceable. Screw (2) Oil Pump Spring Filter O-Ring Down Relief Ball Tilt Relief Valve Removal NOTE: The following procedures requires the use of a Snap-On blind hole removal tool #CG-41-11 with 5/16”...
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POWER TRIM 1. Unscrew plug from manifold and remove spring and poppet assembly. NOTE: Do not lose shim that may be lodged in the plug. 2. Use the removal tool and pull out the pilot valve. Tilt Relief Valve Assembly O-Rings Actuator Pin Pilot Valve...
POWER TRIM Suction Seat Removal 1. Unscrew plug from manifold and remove ball. 2. Use a pin punch and knock the filter and suction seat out from the inside of the manifold cavity. CAUTION DO NOT use any tool on the suction seat as any damage to the surface will not allow the ball to seat.
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Plug (2) Spring (2) Poppet Assembly (2) Seat (2) Spool (1) IMPORTANT: Inspect poppet assemblies for debris in the area shown. If debris is found on poppets replace poppets. Debris Under Valve Tip Rubber Seat Page 5B-40 90-828631R3 MARCH 1999...
POWER TRIM Cleaning/Inspection/Repair IMPORTANT: Components must be dirt and lint free. Slightest amount of debris in Power Trim system could cause system to malfunction. Clean shock rod and components with parts cleaner and dry with compressed air. It is recommended that all O-rings in trim system be replaced. Use O-Ring Kit 25-827668A1. Lubricate all O-rings with power trim fluid.
POWER TRIM Power Trim Reassembly IMPORTANT: Lubricate all O-rings with Quicksilver Power Trim Fluid (92-90100A12). If not available, use automotive (ATF) automatic transmission fluid. Tilt Relief Valve Reassembly 1. Lubricate O-rings with power trim fluid. 2. Place actuator pin into pilot valve. 3.
POWER TRIM Suction Seat Reassembly 1. Lubricate O-rings with power trim fluid. 2. Install filter and suction seat using a 9/32” or 7 mm socket on OUTSIDE diameter of suc- tion seat. 3. Install ball and plug. Torque plug to 120 lb-in. (13.5 Nm). Filter Suction Seat Ball...
POWER TRIM Oil Pump Reassembly 1. Install the down relief ball and spring into manifold. 2. Check to see that O-rings are placed on bottom of pump. 3. Place O-ring (square cut) on filter. 4. Place filter over the oil pump. 5.
POWER TRIM Trim Motor Reassembly 1. Align coupler between oil pump and motor. 2. Install trim motor and secure with four (4) screws. Torque screws to specified torque. Coupler O-ring Trim Pump Motor Ground Strap Lock Washer (1) Screws (4) Screw Torque 80 lb-in.
POWER TRIM Shock Rod Reassembly 1. Install lubricated O-rings to end cap. 2. Install rod wiper. 3. Install lubricated O-rings to shock piston. 51145 51199 Rod Wiper Inner O-ring Outer O-ring Shock Piston O-ring O-ring 4. Clamp shock rod in soft jawed vise. 5.
POWER TRIM 9. Remove shock rod assembly from vise. 10. Install ball, seat, and spring (five sets) to shock rod piston. 51147 Spring (5) Seat (5) Ball (5) 11. Secure components with shock piston bolt. Torque bolt to specified torque. Bolt Bolt Torque 45 lb-ft (61 Nm)
POWER TRIM 3. Fill cylinder three inches (76.2 mm) from top of cylinder using Dexron III, (ATF) automatic transmission fluid. If not available, use Quicksilver Power Trim and Steering Fluid. 4. Install shock rod into cylinder until power trim fluid flows through oil blow off ball passage. Fill remaining cylinder to just below the cylinder threads.
POWER TRIM Bleeding Power Trim Unit 1. Secure power trim unit in soft jawed vise. 2. Remove reservoir plug. Add power trim fluid until it is even with the bottom of the fill hole. Reinstall plug. 3. Close the manual release valve. (Turn full clockwise.) Reservoir Plug 4.
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POWER TRIM 3. Install lower pivot pin. Secure with flat washers and nuts. Torque nuts to specified torque. Nuts Nut Torque 18 lb-ft (24.4 Nm) 4. Install sacrificial anode to clamp brackets. Fasten ground strap between anode and clamp bracket. Torque bolts to specified torque. Ground Wire Sacrificial Anode Bolt Torque...
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POWER TRIM 7. Secure upper pivot pin with trilobe pin. Press trilobe pin in until its fully seated. Trilobe Pin 8. Re-connect trim wire harness leads (see wiring diagram Section 2D for proper connec- tions). 9. Recheck fluid level (tilt/trim rod fully extended). 10.
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O-ring Description and Sizes ....5C-40 Down Circuit ......
POWER TRIM Power Trim NOTE: Lubricate all O-rings using Quicksilver Power Trim and Steering Fluid. If not available, use auto- motive (ATF) automatic transmission fluid. NOTE: It is recommended that all O-rings be replaced when servicing tilt system. Page 5C-4 90-828631R3 MARCH 1999...
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POWER TRIM Power Trim TORQUE REF. REF. QTY. DESCRIPTION lb-in. lb-ft – POWER TRIM PUMP (NON-BIGFOOT) S/N- & UP – POWER TRIM PUMP (BIGFOOT) – POWER TRIM PUMP (NON-BIGFOOT) S/N- & BELOW – POWER TRIM PUMP (BIGFOOT) SHOCK ROD KIT (S/N- & UP) SHOCK ROD KIT (NON-BIGFOOT) S/N- &...
POWER TRIM Theory Of Operation The Power Trim system consists of an electric motor, pressurized fluid reservoir, pump and trim cylinder. The remote control (or trim panel) is equipped with a switch that is used for trimming the outboard “up” and “down”, and for tilting the outboard for shallow water operation (at slow speed) or for “trailering”.
POWER TRIM TRIMMING OUTBOARD “DOWN” (“IN”) WARNING Excessive speed at minimum trim “In” may cause undesirable and/or unsafe steer- ing conditions. Each boat should be tested for handling characteristics after any adjustment is made to the tilt angle (tilt pin relocation). Will help planing off, particularly with a heavy load.
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POWER TRIM Trim Up When the trim switch is activated in the up position, the electric motor (c) begins to rotate the oil pump gears (j), the oil pump draws a small amount of oil through the filter (g) and through the up circuit suction port (i).
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POWER TRIM Tilt Up In the up mode, as the trim rod (a) extends from the cylinder (w), the memory piston (t) clears or uncovers the pressure relief passage. Oil from the up cavity will enter this passage and, if required, causes the tilt relief piston (s) to open the tilt relief valve (r). This valve lowers the amount of pressure available to lift the outboard motor.
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POWER TRIM Maximum Tilt With the trim rod at maximum travel, and due to no rod movement, the pressure inside of the trim cylinder (w) will increase to the pressure required to move the tilt relief piston (s). The tilt relief piston’s “pin” opens the tilt relief valve (r). Up pressure flows allowing the oil to flow into the trim relief passage, and returns back into the reservoir.
POWER TRIM Trim Down When the trim switch is activated in the down position, the electric motor (c) will rotate the oil pump gears (j) in the opposite direction. With the oil pump gears rotating backwards, the flow of oil is reversed. Oil is drawn through the filter (g), through the down circuit suction port (k) and into the oil pump gears (j).
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POWER TRIM Shock Function Up Oil inside the down cavity is locked in a static position by the closed down circuit pressure operated valve (f), the manual release valve (p) and the manifold reverse suction valve (o). If the outboard strikes an underwater object while in forward gear, the trim rod (a) will try to rapidly extend from the cylinder (w), the pressure increases inside the trim cylinder down cavity and connecting passages.
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POWER TRIM Shock Function Return After the engine clears the under water object, the weight of the engine will increase the oil pressure between the memory piston (t) and shock piston (u) to the level required to open the shock return valve (h), inside the shock piston, allowing the oil to bleed back through the shock piston into the down cavity.
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POWER TRIM Manual Tilt To manually tilt the outboard engine, the owner will need to back out the manual release valve (p) 3-4 turns. With the valve backed out, the internal passages inside the manifold are connected together. These passages connect both the cylinder down and up cavities to- gether, along with the reservoir, allowing the engine to be raised or lowered.
POWER TRIM Troubleshooting Support outboard with tilt lock pin when servicing power trim system. IMPORTANT: After debris or failed components have been found (during trouble- shooting procedure), it is recommended that unit be disassembled completely and ALL O-rings be replaced. Check ball valve components and castings must be cleaned using engine cleaner and compressed air or replaced prior to re-assembly.
POWER TRIM Hydraulic System Troubleshooting Flow Chart OUTBOARD WILL NOT HOLD TILTED POSITION DURING REVERSE AND/OR TRAILS OUT DURING HIGH SPEED DECELERATION. Manual release valve and Manual release Inspect manual release valve. O-rings appear to be O.K. - valve and O-ring Clean and reinstall manual damaged.
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POWER TRIM Hydraulic System Troubleshooting Flow Chart continued Remove suction seat as- sembly and inspect for debris and/or damage. Suction seat assembly Debris and/or damage appears O.K. - Clean and identified. reinstall suction seat assembly. Replace suction seat Trim will not hold assembly.
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POWER TRIM Hydraulic System Troubleshooting Flow Chart TRIM SYSTEM LEAKS DOWN WITH MANUAL RELEASE VALVE CLOSED. Manual release valve Inspect manual release valve. Manual release valve and O- and O-ring damaged. rings appear to be O.K. - Clean and reinstall manual release valve.
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POWER TRIM Hydraulic System Troubleshooting Flow Chart continued Inspect memory pis- ton O-ring and cylinder bore. Cylinder bore appears Cylinder bore appears rough and/or debris smooth with no debris. found in cylinder. Replace memory pis- Trim leaks down. ton and shock piston O-rings.
POWER TRIM Troubleshooting the Power Trim Electrical System BLU/WHT GRN/WHT BLU/WHT or PUR GRN/WHT or GRN RED/PUR – RED/PUR GRN/WHT Solenoid BLU/WHT LT. GRN/WHT GRN/WHT 14 BLK LT. GRN/WHT LT. BLU/WHT LT.BLU/WHT BLUE 14 BLK LT. BLU/WHT Trim Switch (Remote Control Mounted) Down Relay Trim Switch (Panel Mounted) Up Relay...
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POWER TRIM Troubleshooting the Power Trim Electrical System Refer to wiring diagram on preceding page for location of wire connections. Problem Possible Cause Remedy Trim Switch “UP” is inopera- 1. Open wire between Wire Connection (1) 1. Check for an open connection or cut tive, but the Cowl Switch and Trim Switch.
POWER TRIM Power Trim System Removal 1. Tilt outboard to the full up position and support with tilt lock pin. 2. Disconnect the power trim wire harness and remove clamp. 55264 55464 Tilt Lock Pin Power Trim Wire Harness Clamp Harness 3.
POWER TRIM 6. Use suitable punch to remove (Drive Down) lower pin. Retain dowel pin. 7. Use suitable punch to drive out lower pivot pin. 51144 51144 Dowel Pin Lower Pivot Pin Power Trim Disassembly IMPORTANT: Power trim system is pressurized. Trim rod must be in the full “UP” position (fully extended) prior to fill/drain plug, or manual release valve removal.
POWER TRIM Trim Motor Removal 1. Secure power trim assembly in a soft jaw vise. 2. Remove four (4) screws to remove motor/reservoir. Remove reservoir seal and coupler. Screw (4) Reservoir Reservoir Seal Coupler Manifold Assembly Pump and Components Removal 1.
POWER TRIM IMPORTANT: Inspect poppet assembly for debris in the area shown. If debris is found on poppet replace poppet. 2. Remove three (3) screws to remove pump. Remove filter and filter seal under pump. Remove suction seat assembly. Debris Under Valve Tip Rubber Seat Screws (3) Filter Seal...
POWER TRIM Shock Rod Removal 1. Unscrew end cap assembly from cylinder using spanner wrench [1/4 in. x 5/16 in. (6.4 mm x 8 mm) long pegs]. 2. Remove shock rod assembly from cylinder. Shock Rod Disassembly NOTE: The only serviceable items on the shock rod assembly are the O-rings and wiper ring.
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POWER TRIM 3. Remove check ball components from shock rod piston. 4. Remove O-ring from shock rod piston. 51147 Spring (5) Seat (5) Ball (5) O-ring CAUTION When removing shock piston, spanner wrench must have 1/4 in. x 5/16 in. long pegs to avoid damage to shock piston.
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POWER TRIM 8. Inspect check valve for debris; clean debris from check valve if found. If debris cannot be cleaned from check valve, replace shock piston as an assembly. 9. Clean shock and components with compressed air. 10. Remove inner O-ring from shock rod piston. 51199 Shock Piston O-ring...
POWER TRIM Memory Piston Removal 1. Remove memory piston from cylinder using one of two methods: a. Using lock ring pliers P/N SRP-4 (Snap-On) or suitable tool. SRP-4 (Snap-On) b. Blowing compressed air into manual release valve hole using air nozzle. WARNING Memory piston cup may be expelled at a high velocity when air pressure is applied.
POWER TRIM Cleaning/Inspection/Repair IMPORTANT: Components must be dirt and lint free. Slightest amount of debris in Power Trim system could cause system to malfunction. Clean shock rod and components with parts cleaner and dry with compressed air. It is recommended that all O-rings in trim system be replaced. Use O-ring Kit 25-809880A1. Lubricate all O-rings with Quicksilver Power Trim Fluid (92-90100A12).
Cap8134) 1.864 in. (47.34 mm) 2.004 in. (50.90 mm) 0.07 in. (1.78 mm) Shock Piston2579) 1.6 in. (40.64 mm) 2.02 in. (53.086 mm) 0.21 in. (5.334 mm) Piston Bolt05797) 0.676 in. (17.17 mm) .816 in. (20.726 mm) 0.07 in. (1.78 mm)
POWER TRIM Power Trim Reassembly IMPORTANT: Lubricate all O-rings with Quicksilver Power Trim Fluid (92-90100A12). If not available, use automotive (ATF) automatic transmission fluid. Shock Rod Reassembly 1. Install lubricated O-rings to end cap. 2. Install rod wiper. 3. Install lubricated O-rings to shock piston. 51145 51199 Rod Wiper...
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POWER TRIM 8. Tighten shock rod piston securely using spanner wrench (1/4 in. x 5/16 in. long pegs). If a torquing type spanner tool is used to tighten shock piston, then torque to specified torque. 51146 Shock Rod Piston Spanner Wrench Shock Piston Torque 90 lb-ft (122 Nm) 9.
POWER TRIM Shock Rod Installation 1. Place trim cylinder in soft jawed vice. 2. Install lubricated O-ring to memory piston and place into cylinder. Push memory piston all the way to bottom. 3. Fill cylinder three inches (76.2 mm) from top of cylinder using Quicksilver Power Trim and Steering Fluid.
NOTE: There are three different size springs used in this manifold. The heavy spring is used on 75-125 hp outboards. The medium spring is used on 40-60 hp Bigfoot outboards. The light spring is used on 30-60 hp outboards.
POWER TRIM Manifold Installation 1. Install dowel pin and two (2) lubricated O-rings into trim cylinder. O-ring (2) Dowel Pin 2. Align the trim cylinder and pump/reservoir assembly together. 3. Install the two (2) long screws and torque to specified torque. 51146 Trim Cylinder Assembly Reservoir/Manifold Assembly...
POWER TRIM Oil Pump Installation 1. Install spring, ball, lubricated O-ring and plastic seat to manifold. 2. Check to see that O-rings are placed on bottom of pump. 3. Install filter and filter seal under pump. Install pump onto manifold. Torque screws to spe- cified torque.
POWER TRIM 2. Install spool, seat with O-ring, check valve/poppet, spring and plug with O-ring into pump. Repeat for other side. Torque plugs to 120 lb-in. (13.5 Nm). Plug (2) Torque to 120 lb-in. (13.5 Nm) Spring (2) Check Valve/Poppet (2) Seat (2) Spool Reservoir/Motor Installation...
POWER TRIM Bleeding Power Trim Unit 1. Secure power trim unit in soft jawed vise. 2. Add power trim fluid until it is even with the bottom of the fill hole. Reinstall plug. 3. Close the manual release valve. (Turn full clockwise). 55263 Reservoir Plug/Fill Hole Manual Release Valve...
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POWER TRIM 3. Position trim cylinder assembly (bottom first) between clamp brackets. 4. Apply 2-4-C Marine Lubricant to lower pivot pin. Using a suitable punch, drive lower pivot pin into clamp bracket and trim cylinder assembly until pivot pin is flush with out- side surface.
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POWER TRIM 7. Using a suitable mallet, drive upper pivot pin into swivel bracket and through trim ram until pivot pin is flush with swivel bracket. 8. Drive pivot pin into its hole until seated. 51148 55464 Pivot Pin Swivel Bracket Trim Ram Trilobe Pin 9.
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POWER TRIM 11. Secure trim harness with clamp, as shown. 55264 Clamp 90-828631R3 MARCH 1999 Page 5C-51...
MANUAL TILT ASSIST Manual Tilt Components 8 11 Loctite 271 (92-809819) 2-4-C With Teflon (92-850736A1) NOTE: Lubricate all O-rings using Quicksilver Power Trim and Steering Fluid. If not avail- able, use automotive (ATF) automatic transmission fluid. NOTE: It is recommended that all O-rings be replaced when servicing tilt system. Page 5D-2 90-828631R3 MARCH 1999...
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MANUAL TILT ASSIST Manual Tilt Components TORQUE REF. REF. QTY. DESCRIPTION lb-in. lb-ft SHOCK ROD ASSEMBLY SHOCK ROD ASSEMBLY (BEACHING) MEMORY PISTON ASSEMBLY O RING REBUILD KIT-Cylinder O RING CYLINDER ASSEMBLY SCREW AND SEAL KIT ACCUMULATOR ASSEMBLY VALVE BODY ASSEMBLY CAM KIT VELOCITY VALVE KIT CHECK SYSTEM REPAIR KIT...
MANUAL TILT ASSIST Manual Trim Flow Diagrams Up Circuit Page 5D-4 90-828631R3 MARCH 1999...
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MANUAL TILT ASSIST Up Circuit With the engine in the down position, the accumulator piston (d) will be at the top of the accu- mulator (c) with the gas at maximum pressure. To raise the engine, the camshaft lever (f) is rotated all the way down.
MANUAL TILT ASSIST Down Circuit Page 5D-6 90-828631R3 MARCH 1999...
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MANUAL TILT ASSIST Down Circuit With the engine tilted up, the piston inside the accumulator piston (d) will be at the bottom of the accumulator (c) and the gas pressure is low. To lower the engine, the camshaft lever (f) is rotated down, the internal cam will cause the push rods to open the accumulator check valve (e), both fast transfer valves (h &...
MANUAL TILT ASSIST Slow Tilt Down Under High Thrust Page 5D-8 90-828631R3 MARCH 1999...
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MANUAL TILT ASSIST Slow Tilt Down Under High Thrust To tilt the engine down under high thrust conditions [where the propeller thrust forces the shock rod down, creating higher pressure below the memory piston (m)], the camshaft lever (f) is rotated slightly downward. The internal shaft connected to the lever will open the down circuit slow transfer valve (i) allowing oil under pressure into the cavity around the shaft.
MANUAL TILT ASSIST Under Water Strike (Valves Open) Page 5D-10 90-828631R3 MARCH 1999...
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MANUAL TILT ASSIST Under Water Strike (Valves Open) Should the drive unit strike a submerged object while in forward motion, the shock rod (a) will extend from the tilt cylinder (l). Fluid will attempt to exit the cylinder through the intercon- necting passage.
MANUAL TILT ASSIST Shock Function (Valves Closed) Accumulator Gas Pressure 400 psi Page 5D-12 90-828631R3 MARCH 1999...
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MANUAL TILT ASSIST Shock Function (Valves Closed) Should the drive unit strike a submerged object while in forward motion, the shock rod (a) will extend from the cylinder (l). Oil inside the up cavity is locked in a static position by the closed up circuit fast transfer valve (j), the closed down circuit slow transfer valve (i) and closed down circuit fast transfer valve (h).
MANUAL TILT ASSIST Shock Function Return Page 5D-14 90-828631R3 MARCH 1999...
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MANUAL TILT ASSIST Shock Function Return After the drive clears the object, the shock return valve (o) will allow the oil to flow from be- tween the shock piston (n) and memory piston (m) onto the down cavity as the drive returns to its original running position.
MANUAL TILT ASSIST Hydraulic System Troubleshooting Refer to disassembly/reassembly instructions (following) if disassembly is required when servicing. IMPORTANT: After debris or failed components have been found (during trouble- shooting procedure), it is recommended that unit be disassembled completely and all O-rings be replaced. Check ball components and castings must be cleaned using engine cleaner and compressed air or replaced prior to reassembly.
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MANUAL TILT ASSIST 2. Check for external leaks in the manual tilt system. Replace defective part(s) if leak is found. IMPORTANT: If cut or damaged O-rings are found, inspect machined surfaces for scoring, burrs or debris. 3. Check for discharged accumulator. 35 to 50 lb-ft (47-68 Nm) of pulling force must be at- tained when tilting outboard from full “down”...
MANUAL TILT ASSIST Manual Tilt System Removal CAUTION Remove cowling and remove all spark plug leads from spark plugs to prevent acci- dental starting while servicing outboard. WARNING Service or installation of the tilt system may result in loss of pressure in the shock cylinder.
MANUAL TILT ASSIST Accumulator Removal 1. Place manual tilt system in soft jawed vise. 2. Position shock rod to full up position. 3. Open cam shaft valve (Down Position). 4. Loosen velocity valve enough to drip, wait until dripping stops. 5.
MANUAL TILT ASSIST Shock Rod Removal 1. Unscrew cylinder end cap assembly using spanner wrench [1/4 in. x 5/16 in. long pegs]. 2. Remove shock rod assembly from cylinder. 91-74951 51145 Shock Rod Disassembly NOTE: The only serviceable items on the shock rod assembly are the O-rings and wiper ring.
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MANUAL TILT ASSIST 3. Remove check ball components from shock rod piston. 4. Remove O-ring. 51147 Spring (5) Seat (5) Ball (5) O-ring CAUTION When removing shock piston, spanner wrench must have 1/4 in. x 5/16 in. long pegs to avoid damage to shock piston. 5.
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MANUAL TILT ASSIST 8. Inspect check valve for debris; clean debris from check valve if found. If debris cannot be cleaned from check valve, replace shock piston as an assembly. 9. Clean shock and components with compressed air. 10. Remove inner O-ring. 51199 Shock Piston O-ring...
MANUAL TILT ASSIST Valve Block Removal 1. Remove two screws from the shock rod cylinder to separate the valve block. 2. Remove O-rings and dowel pins. 51148 51146 Screw Valve Block Shock Rod Cylinder O-ring (2) Dowel Pin (2) Memory Piston Removal 1.
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MANUAL TILT ASSIST b. Blowing compressed air into center O-ring hole. WARNING Memory piston cup may be expelled at a high velocity when air pressure is applied. Failure to place cylinder as shown below could result in personal injury. NOTE: Point cylinder opening down and away. Use a shop rag or towel to avoid damage to the memory piston.
MANUAL TILT ASSIST Reassembly - O-Ring and Seal Placement 11 12 NOTE: Lubricate all O-rings using Quicksilver Power Trim and Steering Fluid. If not avail- able, use automotive (ATF) automatic transmission fluid. NOTE: It is recommended that all O-rings be replaced when servicing tilt system. 90-828631R3 MARCH 1999 Page 5D-27...
Cyl. Cap 1.864 in. (47.34 mm) 2.004 in. (50.90 mm) 0.07 in. (1.78 mm) Shock Piston 1.6 in. (40.64 mm) 2.02 in. (53.086 mm) 0.21 in. (5.334 mm) Piston Bolt 0.676 in. (17.17 mm) .816 in. (20.726 mm) 0.07 in. (1.78 mm)
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MANUAL TILT ASSIST CAM SHAFT REASSEMBLY IMPORTANT: Cam shaft O-ring must be lubricated using 2-4-C with Teflon. 1. Install lubricated O-ring and back up seal to cam. 2. Install shaft seal in valve block with lips facing out. 3. Install cam shaft assembly in valve block. 4.
MANUAL TILT ASSIST Shock Rod Reassembly 1. Install lubricated O-rings to end cap. 2. Install rod wiper. 3. Install lubricated O-rings to shock piston. 51145 51199 Rod Wiper Inner O-ring Outer O-ring Shock Piston O-ring O-ring 4. Clamp shock rod in soft jawed vise. 5.
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MANUAL TILT ASSIST CAUTION hen installing shock rod piston, spanner wrench must have 1/4 in. x 5/16 in. (6.4mm x 8mm) long pegs to avoid damage to shock rod piston. 6. Apply Loctite Grade “A” (271) to threads on shock rod. 7.
MANUAL TILT ASSIST Shock Rod Installation and Fluid Filling Procedure NOTE: There are two ways for the filling procedure. The first is the easiest and less time consuming. Filling Procedure Option One 1. Place trim cylinder in soft jawed vice. 2.
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MANUAL TILT ASSIST 8. Open and close cam lever, watching for bubbles coming from accumulator check ball hole. When bubbles stop, fill accumulator opening to top with fluid. Grease threads on accumulator and opening with 2-4-C with Teflon. Start accumulator in threads and open cam lever (Down Position).
MANUAL TILT ASSIST Filling Procedure Option Two Instructions for Making Retaining Tool 3/16 in x 3 in. (5 x 7.5 cm) Steel Plate 3/8 in. x 13 in. (10 mm x 33 cm) Threaded Rod 4in. x 1/4 in. min. (10cm x 6.4 mm) minimum Channel Iron 10 in.
MANUAL TILT ASSIST Bleeding Manual Tilt System IMPORTANT: While bleeding tilt system, time must be allowed between each stroke to allow air bubbles to dissipate. 1. With shock rod in the full up position and manifold cam lever open (facing down), secure tilt system to retaining tool and container.
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MANUAL TILT ASSIST 4. During up stroke, pull up on rod slowly 3 in. (76 mm) from base. 5. Wait until all air bubbles to exit accumulator base. 50433 6. Slowly cycle unit 5-8 times (round trip per cycle) using short strokes 3 in. (76 mm) from base allowing bubbles to disappear during each stroke.
2. Start lower pivot pin into pivot pin hole and position lower dowel pin (retained) in its hole. 3. Reinstall manual tilt system, bottom first. Reconnect release valve link rod. 51148 51144 2-4-C w/Teflon (92-850736A1) Lower Pivot Pin Lower Dowel Pin Manual Tilt System Page 5D-40 90-828631R3 MARCH 1999...
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MANUAL TILT ASSIST 4. Using a suitable punch, drive lower pivot pin into clamp bracket and trim cylinder assem- bly until pivot pin is flush with outside surface. 5. Using a punch, drive lower dowel pin in until seated. 51148 51147 Lower Pivot Pin Lower Dowel Pin...
MANUAL TILT ASSIST 8. Drive upper dowel pin (a) into its hole until seated. 51147 Dowel Pin 9. Check manual release cam adjustment. Cam must open and close freely. Adjust link rod as necessary. Manual Release Valve Adjustment 1. With outboard in full up position, place tilt lock lever forward. 2.
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NON-BIGFOOT GEAR HOUSING General Service Recommendations There may be more than one way to “disassemble” or “reassemble” a particular part(s), therefore, it is recommended that the entire procedure be read prior to repair. IMPORTANT: Read the following before attempting any repairs. In many cases, disassembly of a sub-assembly may not be necessary until cleaning and inspection reveals that disassembly is required for replacement of one or more components.
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NON-BIGFOOT GEAR HOUSING Draining and Inspecting Gear Lubricant WARNING If gear housing is installed on outboard, disconnect (and isolate) spark plug leads from spark plugs before working near the propeller. 1. With gear housing in normal running position, place a clean pan under housing and remove vent plug and fill/drain plug (with gaskets).
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1. Remove (and isolate) spark plug leads from spark plugs. 2. Shift into NEUTRAL. 2-Stroke Models MERCURY/MARINER 30/40, AND 40/50 FORCE 40/50 3. Loosen jam nut. Unscrew attaching nut to separate shift shaft. 52832...
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NON-BIGFOOT GEAR HOUSING 4-Stroke Models MERCURY/MARINER 25, 30/40, AND 45/50 4. Disconnect shift shaft by un-snapping retainer to lower clip and sliding retainer to the left. Retainer Lower Clip 5. Make a scribe line showing alignment of trim tab to gear case and remove trim tab bolt and washer.
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NON-BIGFOOT GEAR HOUSING 6. Remove nut and washer in trim tab cavity. 52835 Nut and Washer 7. Remove 4 bolts securing gear case to drive shaft housing. 52836 Bolt (4) Page 6A-14 90-828631R3 MARCH 1999...
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NON-BIGFOOT GEAR HOUSING Disassembly Water Pump NOTE: If water tube seal remained in drive shaft housing, remove seal from housing and reinstall on water pump cover. Secure seal to cover with Loctite 405. 1. Remove 4 bolts securing pump cover. 52830 Seal Bolt (4)
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NON-BIGFOOT GEAR HOUSING 2. Remove cover, washer (above impeller), impeller, key and washer (below impeller). 3. Remove cover gasket, base plate and base gasket. 52692 Cover Nylon Washer (above impeller) Impeller Nylon Washer (below impeller) Cover Gasket Face Plate Base Gasket NOTE: Replace impeller if: –...
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NON-BIGFOOT GEAR HOUSING 4. Remove and/or replace exhaust deflector plate if damaged. 52832 Deflector Plate 5. Inspect auxiliary water inlet tube for excessive corrosion/erosion. Replace as required. 57830 Water Inlet Tube 90-828631R3 MARCH 1999 Page 6A-17...
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NON-BIGFOOT GEAR HOUSING 6. Remove bearing carrier attaching bolts and locking tab washers or flat washers. Discard tab washers. Bolts and Tab Washers or Flat Washers Tab Washers Style 2 7. Using Puller (91-27780), remove carrier assembly from gear case. 91-27780 52829 Puller (91-27780)
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NON-BIGFOOT GEAR HOUSING 13. Insert spring hook (91-825200A1) or bearing cup puller (91-859749) through gear case and position inside of pinion bearing race. Insert driver (91-13779) into spring hook or driver (91-44385) into bearing cup puller through drive shaft cavity and drive out race. 52844 57829 91-44385...
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NON-BIGFOOT GEAR HOUSING Water Pump Seals NOTE: All gaskets, seals and O-rings should be replaced as a normal repair procedure dur- ing gear case disassembly. NOTE: DO NOT use a screwdriver to remove seals from carrier, as carrier may be dam- aged.
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NON-BIGFOOT GEAR HOUSING 3. With lip of ribbed neoprene O.D. seal facing towards small shoulder of Mandrel (91-825197), press seal into carrier until mandrel bottoms on carrier. 91-825197 52853 Seal (Ribbed Neoprene) Lip Facing Up Mandrel (91-825197) NOTE: Apply a light coat of 2-4-C w/Teflon (92-850736A1) to the lips of both seals after installation in carrier.
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NON-BIGFOOT GEAR HOUSING Inspection Upper Drive Shaft Bearing 1. Inspect bearing for rust, roughness or discoloration from lack of lubricant. 2. DO NOT remove bearing from drive shaft unless bearing must be replaced, as removal process will damage bearing. 3. If bearing must be replaced, position drive shaft assembly in vise (jaws of vise support- ing only bearing) and while holding drive shaft, strike top of drive shaft with lead hammer and drive bearing off.
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NON-BIGFOOT GEAR HOUSING Pinion Gear Bearing 1. Inspect bearing for rust, roughness or discoloration from lack of lubricant. 2. If bearing is damaged, bearing and race must be replaced as an assembly. 3. If race appears to have spun in drive shaft bore, gear case housing must be replaced. 52823 Bearing Race...
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NON-BIGFOOT GEAR HOUSING 3. Inspect propeller shaft forward gear bearing surface to determine condition of forward gear needle bearing. If bearing surface is discolored (from lack of lubricant), pitted or worn, propeller shaft and bearing should be replaced. 52874 52846 Bearing Surface Bearing 4.
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NON-BIGFOOT GEAR HOUSING 6. Inspect forward gear tapered bearing and race for rust, roughness or excessive wear (looseness). 7. If bearing is in serviceable condition, DO NOT remove bearing from gear, as removal process will damage bearing. 8. If bearing must be replaced, remove bearing from gear using Universal Puller Plate (91-37241) and suitable mandrel.
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NON-BIGFOOT GEAR HOUSING Shift Shaft 1. Inspect shift cam for wear or galling. Replace cam if necessary. 2. If cam is worn, inspect cam follower in end of propeller shaft for wear. 52845 Cam Follower Shift Cam 3. Inspect shift shaft boot for deterioration. 4.
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NON-BIGFOOT GEAR HOUSING Propeller Shaft Disassembly 1. Remove propeller shaft from carrier and disassemble shaft. Prop Shaft Retaining Spring Clutch Dog Cross Pin Cam Follower Spring Cam Follower 2. Remove reverse gear and bearing from carrier with Puller (91-27780). 91-27780 52840 Reverse Gear and Bearing Puller (91-27780)
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NON-BIGFOOT GEAR HOUSING Propeller Shaft and Carrier Inspection Clutch 1. Inspect clutch dogs for chips or rounding off. 2. If wear is present, inspect corresponding forward or reverse gear matching dogs for sim- ilar wear. Replace appropriate components as required. 52824 Cam Follower 1.
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NON-BIGFOOT GEAR HOUSING Reverse Gear Bearing 1. Inspect bearing for rust, roughness or excessive wear (looseness). 2. If bearing is in serviceable condition, DO NOT remove bearing from gear as removal will damage bearing. 3. If bearing must be replaced, remove bearing from gear using Universal Puller Plate (91-37241) and Driver (91-37312).
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NON-BIGFOOT GEAR HOUSING Bearing Carrier NEEDLE BEARING 1. The condition of the carrier needle bearing can be determined by inspecting its running surface on the propeller shaft. 2. If the shaft is discolored (from lack of oil) or pitted, replace bearing and shaft. 3.
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NON-BIGFOOT GEAR HOUSING 6. Press bearing into carrier until mandrel bottoms on carrier. NOTE: Press on number side of bearing. 91-817011 52861 Super Duty Gear Lubricant (92-850737A1) Bearing Mandrel (91-817011) 7. Apply Loctite 271 to O.D. of small diameter seal. 8.
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NON-BIGFOOT GEAR HOUSING 9. Apply Loctite 271 to O.D. of large diameter seal. 10. With seal lip FACING TOWARDS SMALL SHOULDER of Mandrel 91-817007, press seal into carrier until mandrel bottoms on carrier. 91-817007 52863 Loctite “271” (92-809819) Seal Mandrel (91-817007) Installation Note: If service tools are not available, the following reference dimensions ap- ply for installing bearing and seals to proper depths.
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NON-BIGFOOT GEAR HOUSING 11. Bearing carrier O-ring should be inspected for cuts and abrasions. NOTE: It is a good repair procedure to replace all O-rings and seals regardless of appear- ance. 12. Apply 2-4-C w/Teflon to O.D. of bearing carrier and also to O-ring. Install O-ring onto bearing carrier.
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NON-BIGFOOT GEAR HOUSING Gear Housing Reassembly IMPORTANT: This gear case assembly does not have have any shims for the gear as- semblies. Backlash cannot be adjusted. The mechanic must verify that all bearing races are firmly seated in the gear case during reassembly and that all gear case com- ponents are in serviceable condition.
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NON-BIGFOOT GEAR HOUSING Pinion Bearing Race 1. Apply Super Duty Gear Lubricant to O.D. of race. 2. Position race in gear housing (NUMBERS UP - TAPERED SIDE FACING DOWN). 3. Draw race up into housing until seated. 12-34961 11-24156 91-31229 91-29310 31-85560 91-825199...
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NON-BIGFOOT GEAR HOUSING Forward Gear 1. Apply Super Duty Gear Lubricant to O.D. of race. Install forward gear bearing race into housing using Mandrel 91-36571 and propeller shaft. Use a lead hammer on prop shaft to prevent damage to threads. Bearing carrier should be installed to keep prop shaft centered while seating race.
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3. Apply Loctite 271 to pinion nut threads. 4. Install new pinion nut, with rounded corners FACING pinion gear, onto drive shaft. Models Drive Shaft Holding Tool 4-Stroke 91-83180M Mercury/Mariner 25, 30/40, and 45/50 2-Stroke Force 40/50 91-825196 Mercury/Mariner 30/40, 40/50 5.
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4. Remove wrench and press cross pin through clutch and propeller shaft until flush. 52851 Short Shoulder Allen Wrench Cross Pin 5. Reinstall retaining spring. position spring so as spring coils lay flat in clutch groove. Spring Page 6A-40 90-828631R3 MARCH 1999...
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NON-BIGFOOT GEAR HOUSING NOTE: Applying 2-4-C w/Teflon to cam follower will aid in retention of follower in propeller shaft during installation of propeller shaft assembly into gear case. 6. Install cam follower. 52826 2-4-C w/Teflon (92-850736A1) Cam Follower 7. Install propeller shaft assembly into gear case. 52864 Propeller Shaft Assembly 90-828631R3 MARCH 1999...
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..0G650699 and below Belgium ..Force 40/50 (2 Cylinder - 2 Stroke) ..0E323508 and below Bolt 25 mm Long - Discard Tab Washer - Discard Thin Flat Washer 0.063 in.
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NON-BIGFOOT GEAR HOUSING 4. Torque bolts to specified torque. Loctite “271” (92-809819) Bolts Bearing Carrier Bolt Torque 18.8 lb-ft (25.4 Nm) Water Pump 1. Install water pump seal carrier. 2. Install exhaust deflector plate, if removed. 52832 Seal Carrier Exhaust Deflector 90-828631R3 MARCH 1999 Page 6A-43...
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NON-BIGFOOT GEAR HOUSING 3. Install base gasket, face plate, pump cover gasket (NEOPRENE STRIP FACES UP), nylon washer and impeller key. 52868 Base Gasket Base Plate Cover Gasket Neoprene Strip Nylon Washer IMPORTANT: If impeller being installed has been previously used and vanes have tak- en a “set,”...
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NON-BIGFOOT GEAR HOUSING 4. Install impeller and nylon washer. 52869 Impeller Nylon Washer NOTE: Apply a light coat of 2-4-C w/Teflon to inside of pump cover to ease installation of cover over impeller. 5. Install pump cover. Rotate drive shaft CLOCKWISE while pressing cover down over im- peller.
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NON-BIGFOOT GEAR HOUSING Gear Housing Pressure Test 1. Remove vent plug and install pressure test gauge. Tighten securely. 2. Pressurize housing to 10-12 psi (69-83 kPa) and observe gauge for 5 minutes. 3. Rotate drive shaft, prop shaft and move shift rod while housing is pressurized to check for leaks.
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5. Install 4 bolts and washers, (two each side). Torque bolts to specified torque. 52836 Bolt and Washers (2 each side) Gear Housing Bolt Torque 40 lb-ft (54.2 Nm) 90-828631R3 MARCH 1999 Page 6A-47...
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52834 Coupler Nut Jam Nut Spray Plate 4-Stroke Models MERCURY/MARINER 25, 30/40, AND 45/50 7. Connect shift shaft by sliding retainer to the right and snapping into upper “locked” position. 53859 Retainer Lower Clip Page 6A-48...
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8. Install locknut and washer. Torque nut to specified torque. 52833 Locknut and Washer Nut Torque 40 lb-ft (54.2 Nm) 9. Check shift operation. a. In NEUTRAL, propeller shaft should turn freely in either direction. b. In FORWARD, propeller shaft SHOULD NOT TURN COUNTERCLOCKWISE.
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NON-BIGFOOT GEAR HOUSING b. If boat pulls to the left, adjust trailing edge of trim tab to the left. If boat pulls to the right, adjust trailing edge of trim tab to the right. 52835 Trim Tab Anti-Ventilation Plate Retaining Bolt and Washer Bolt Torque 15.8 lb-ft (21.4 Nm) Page 6A-50...
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NON-BIGFOOT GEAR HOUSING Filling Gear Housing with Lubricant NOTE: Gear housing lubricant capacity is approximately 14.9 fl oz (440 ml). WARNING If gear housing is installed on outboard, disconnect (and isolate) spark plug leads from spark plugs before working near the propeller. CAUTION Do not use automotive grease in the gear housing.
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......6B-8 Driveshaft Wear Sleeve Installation ..6B-40 General Service Recommendations ..6B-10...
BIGFOOT GEAR HOUSING General Service Recommendations There may be more than one way to “disassemble” or “reassemble” a particular part(s), therefore, it is recommended that the entire procedure be read prior to repair. IMPORTANT: Read the following before attempting any repairs. In many cases, disassembly of a sub-assembly may not be necessary until cleaning and inspection reveals that disassembly is required for replacement of one or more components.
BIGFOOT GEAR HOUSING Draining and Inspecting Gear Lubricant WARNING If gear housing is installed on engine, to avoid accidental starting, disconnect (and isolate) spark plug leads from spark plugs before working near the propeller. 1. With gear housing in normal running position, place a clean pan under housing and re- move the two vent screws and one fill/drain screw (with gaskets).
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BIGFOOT GEAR HOUSING Removal WARNING To prevent accidental engine starting, remove (and isolate) spark plug leads from spark plugs before removing gear housing. 1. Remove (and isolate) spark plug leads from spark plugs. 2. Shift engine into forward gear. 3. Tilt engine to full “Up” position. 4.
BIGFOOT GEAR HOUSING Disassembly Water Pump NOTE: If water tube seal stayed on water tube (inside of driveshaft housing) when gear housing was removed, pull water tube seal from water tube. 1. Replace water tube seal, if damaged. 2. Remove 4 bolts, washers, and isolators. 3.
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BIGFOOT GEAR HOUSING 6. Inspect impeller. Replace impeller if any of the following conditions exist: Impeller blade(s) are cracked, torn, or worn. Impeller is glazed or melted (caused by operation without sufficient water supply). Rubber portion of impeller is not bonded to impeller hub. 7.
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BIGFOOT GEAR HOUSING 10. Remove water pump base. 19226 Water Pump Base 11. Remove (and discard) seals. 19195 Seals 12. Remove gasket. 19218 Gasket 90-828631R3 MARCH 1999 Page 6B-15...
BIGFOOT GEAR HOUSING Bearing Carrier and Propeller Shaft 1. Remove fasteners. 51117 Fasteners 2. With propeller shaft horizontal, pull carrier to break seal with gear housing. Remove bearing carrier/propeller shaft components as an assembly, taking care not to lose cam follower or 3 metal balls in end of propeller shaft.
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BIGFOOT GEAR HOUSING 4. Lift reverse gear, thrust bearing and thrust washer from bearing carrier. 5. Replace reverse gear if gear teeth or clutch teeth on reverse gear are chipped or worn. If reverse gear must be replaced, pinion gear and sliding clutch should be inspected for damage.
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BIGFOOT GEAR HOUSING 8. If bearing is rusted or does not roll freely, replace bearing. Remove bearing and oil seals using Mandrel* (91-36569) and Driver Rod* (91-37323). Discard oil seals. NOTE: From Bearing Removal and Installation Kit (91-31229A7) 91-36569 91-37323 51264 Bearing Mandrel (91-26569)
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BIGFOOT GEAR HOUSING 10. Remove spring. 51876 Spring 11. Apply constant pressure to cam follower to prevent cam follower assembly from ejecting from propeller shaft while pushing cross pin out of clutch dog. 51800 Cross Pin Cam Follower 90-828631R3 MARCH 1999 Page 6B-19...
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BIGFOOT GEAR HOUSING 12. Remove components from propeller shaft. 13. Replace cam follower if worn or pitted. 14. Replace sliding clutch if jaws are rounded or chipped. Rounded jaws indicate one or more of the following: Improper shift cable adjustment. Engine idle speed too high while shifting.
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BIGFOOT GEAR HOUSING Pinion Gear, Driveshaft, and Forward Gear 1. Hold driveshaft using Driveshaft Holding Tool; remove (and discard) pinion nut. Model Driveshaft Holding Tool 40/50 Bigfoot (4-Stroke) 91-56775 60 Bigfoot 91-817070 75/90/100/115/125 91-56775 2. Remove driveshaft, pinion gear, bearing and forward gear.
BIGFOOT GEAR HOUSING 6. Replace bearing if it is rusted or does not roll freely; use a punch and hammer to remove bearing. 19203 Bearing 7. Replace forward gear bearing and race if either are rusted, pitted or damaged; or if bear- ing does not roll freely.
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BIGFOOT GEAR HOUSING 8. Replace driveshaft if splines are worn or twisted. 9. If bearing surface is damaged, replace driveshaft and corresponding bearing. IMPORTANT: Do not tighten vise against driveshaft. 10. If wear sleeve is deeply grooved allowing water to enter gear case, remove (and discard) sleeve using Universal Puller Plate (91-37241) and mallet.
BIGFOOT GEAR HOUSING Upper Driveshaft Bearing 1. Replace upper driveshaft bearing and sleeve if either are rust stained, or if bearing will not roll freely. Remove bearing and then sleeve using Puller Assembly (91-83165M) with suitable jaws. 91-83165M 19177 Upper Driveshaft Bearing Sleeve Puller Assembly (91-83165M) IMPORTANT: Upper driveshaft bearing/sleeve must be removed prior to oil sleeve re-...
BIGFOOT GEAR HOUSING Oil Sleeve 1. Remove oil sleeve (if necessary) using Puller Assembly (91-83165M) with suitable jaws. 91-83165M 19222 Oil Sleeve Puller Assembly (91-83165M) IMPORTANT: Upper driveshaft bearing/sleeve and oil sleeve do not have to be re- moved for lower driveshaft bearing race removal. 90-828631R3 MARCH 1999 Page 6B-25...
BIGFOOT GEAR HOUSING Forward Gear Bearing Race IMPORTANT: Retain shim(s) for reassembly. If shims are damaged, replace with new shims of equal thickness. 1. Remove race and shim(s) using Slide Hammer (91-34569A1). 91-34569A1 27653 Race Shim(s) Slide Hammer (91-34569A1) Trim Tab Adjustment and Replacement IMPORTANT: The trim tab is now painted and does NOT aid in protecting the drive- shaft housing and gear housing from galvanic corrosion (corrosion and pitting of metal surfaces).
BIGFOOT GEAR HOUSING Reassembly Forward Gear Bearing Race 1. Place shim(s) (retained from disassembly) into housing. If shim(s) were lost, or a new gear housing is being assembled, start with 0.010 in. (0.254 mm) shim(s). 2. Assemble components as shown using mandrel (91-31106); Apply 2-4-C w/Teflon to O.D.
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BIGFOOT GEAR HOUSING 5. Assemble components as shown. 53928 Shift Shaft “E” Clip Shift Shaft Bushing 6. Install shift cam; align hole in shift cam with hole in gear housing. 60 Bigfoot 75/90/100/115/125 51117 Shift Cam (marked with “UP” and part number) Gear Housing Hole 60 Bigfoot 75/90/100/115/125 51117...
Page 538
BIGFOOT GEAR HOUSING 40/50 Bigfoot (4-Stroke) 850307 51117 Shift Cam (Numbers Down) Hole 7. Install shift shaft assembly; insert splines into shift cam. 53932 Shift Shaft Assembly Splines 8. Apply Loctite 271 on bottom half of threads of bolts; install bolts and torque to specified torque.
BIGFOOT GEAR HOUSING Bearing Carrier Reassembly 1. Lubricate O.D. of bearing and bearing carrier bore with Quicksilver 2-4-C w/Teflon. 2. Protect lip on forward side of bearing carrier, using bearing installation tool (91-13945). 3. Press propeller shaft needle bearing (number side toward mandrel 91-15755) into carrier, until bearing bottoms out.
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BIGFOOT GEAR HOUSING 4. Place smaller diameter seal on longer shoulder of Oil Seal Driver (91-31108) with seal lip away from shoulder. 5. Protect lip on front side of bearing carrier using Bearing Installation Tool (91-13945). Apply Loctite 271 on O.D. of seal. Press seal into carrier until tool bottoms. 91-31108 91-13945 Loctite “271”...
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BIGFOOT GEAR HOUSING 8. Install O-ring. Lubricate O-ring with 2-4-C w/Teflon. Lubricate seal lips with 2-4-C w/Teflon. 9. Lubricate outside diameter of reverse gear bearing and bearing carrier bore with a light coating of 2-4-C w/Teflon. 10. Press bearing into carrier until tool bottoms. 91-13945 19163 2-4-C w/Teflon (92-850736A1)
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BIGFOOT GEAR HOUSING 12. Install thrust bearing. Coat thrust bearing with Super Duty Gear Lubricant. 19168 Super Duty Gear Lubricant (92-850737A1) Thrust Bearing 13. Apply Super Duty Gear Lubricant to bearing surface of reverse gear and install reverse gear. 19202 Super Duty Gear Lubricant (92-850737A1) Reverse Gear Bearing Surface...
BIGFOOT GEAR HOUSING Forward Gear Reassembly 1. Press bearing onto gear using mandrel 91-37350 (press only on inner race of bearing). 91-37350 51869 2-4-C w/Teflon (92-850736A1) Mandrel (91-37350) Bearing; Lubricate I.D. with Quicksilver 2-4-C w/Teflon 2. Inspect reverse gear end of clutch to determine the number of jaws. Refer to chart, fol- lowing, for tool end selection.
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BIGFOOT GEAR HOUSING 6 Jaw Reverse Clutch 56784 Stamped “6” Numbered end of Needle Bearing 6 Jaw Reverse Clutch 3. Apply Quicksilver gear lubricant to I.D. of forward gear. Press bearing into forward gear until tool contacts gear. 56785 Quicksilver Gear Lubricant (92-19007A24) Forward Gear Bearing Installer (91-856875) Needle Bearing, Numbered Side Toward Installer Tool Page 6B-38...
BIGFOOT GEAR HOUSING Propeller Shaft Reassembly 1. Install components into propeller shaft in sequence shown. 19154 Spring Guide Block 3 Metal Balls* Cam Follower* *Hold in Place With Quicksilver 2-4-C w/Teflon 2. Install cross pin. 51800 Apply Pressure in This Direction Cross Pin 3.
2. Apply a light coat of Loctite 271 on outside diameter of rubber ring. 19152 Loctite “271” (92-809819) Ring 3. Insert sleeve into holder*. *Component of Wear Sleeve Installation Tool (91-14310A1). 91-14310A1 19169 Sleeve Holder Page 6B-40 90-828631R3 MARCH 1999...
BIGFOOT GEAR HOUSING Lower Driveshaft Bearing Race Installation IMPORTANT: Lower driveshaft bearing cup can be installed with or without upper driveshaft bearing/sleeve and oil sleeve installed. 1. Lubricate O.D. of bearing race with Quicksilver 2-4-C w/Teflon. 2. Install shim(s) and bearing race into housing. NOTE: Verify shim(s) are not cocked when drawing up race.
BIGFOOT GEAR HOUSING Oil Sleeve Installation 1. Install oil sleeve with tab positioned as shown. 53934 Oil Sleeve Upper Driveshaft Bearing Installation 1. Lubricate I.D. of bearing holder and O.D. of bearing with 2-4-C w/Teflon. 2. Press bearing into sleeve using mandrel from bearing installation tool (91-14309A1). 91-13781 19164 2-4-C w/Teflon (92-850736A1)
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BIGFOOT GEAR HOUSING IMPORTANT: Oil sleeve must be installed prior to upper drive bearing installation. IMPORTANT: Upper driveshaft bearing/sleeve can be installed with or without lower driveshaft bearing cup installed. 3. Install bearing/sleeve into housing. 91-14310A1 53935 Bearing/Sleeve Tapered End Mandrel* (13781) Mandrel* (13780) Threaded Rod** (91-31229)
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Installation 1. Install components in sequence shown. 19175 Loctite “271” (92-809819) Super Duty Gear Lubricant (92-850737A1) Model Driveshaft Holding Tool 40/50 Bigfoot (4-Stroke) 91-56775 60 Bigfoot 91-817070 75/90/100/115/125 91-56775 Forward Gear/Bearing: Work Quicksilver gear lube into bearing rollers. Lower Driveshaft Tapered Roller Bearing: Work Super Duty Gear Lube into bearing rollers.
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BIGFOOT GEAR HOUSING Pinion Gear Depth and Forward Gear Backlash DETERMINING PINION GEAR DEPTH NOTE: Read entire procedure before attempting any change in shim thickness. IMPORTANT: Forward gear assembly must be installed in gear housing when check- ing pinion gear depth or an inaccurate measurement will be obtained. 1.
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9. Insert tool into forward gear assembly; position proper numbered flat (from chart) of gauging block – under pinion gear. MODEL GEAR RATIO (PINION GEAR USE FLAT NO. LOCATING DISC NO. TEETH/REVERSE GEAR TEETH) 40/50 Bigfoot (4-stroke) 2.31:1 (13/30) 60 Bigfoot/60 Seapro/60 2.31:1 (13/30) Marathon 75-thru-90 2.31:1 (13/30)
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BIGFOOT GEAR HOUSING 10. Install locating disc against bearing carrier shoulder in gear housing. 11. Position access hole as shown. Disc 3 24643 Locating Disc Access Hole 12. Determine pinion gear depth by inserting a feeler gauge thru access hole in locating disc.
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BIGFOOT GEAR HOUSING DETERMINING FORWARD GEAR BACKLASH NOTE: Read entire procedure before attempting any change in shim thickness. 1. Obtain correct pinion gear depth; refer to “Determining Pinion Gear Depth,” preceding. 2. Install Bearing Preload Tool (91-14311A2) on driveshaft; refer to “Determining Pinion Gear Depth,”...
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Backlash Indicator Tool 6. Position Dial Indicator on appropriate line (from chart) marked on Backlash Indicator Tool. BACKLASH INDICATOR ALIGN POINTER OF DIAL INDICATOR MODEL TOOL WITH MARK 40/50 Bigfoot 91-78473 (4-Stroke) 60 Seapro/60 Mara- 91-78473 thon/60 Bigfoot 75-thru-90 91-78473...
7. Lightly turn driveshaft back-and-forth (no movement should be noticed at propeller shaft). 8. Dial Indicator registers amount of backlash, which must be between specification shown in chart. MODEL DIAL INDICATOR MINIMUM READING MAXIMUM 40/50 Bigfoot 0.012 in. 0.019 in. (4-Stroke) (0.30 mm) (.48 mm) 0.012 in.
Page 558
BIGFOOT GEAR HOUSING 3. Lubricate O-ring and mating surfaces with 2-4-C w/Teflon. 4. Install bearing carrier and propeller shaft into housing with the word “TOP” located on flange toward top of housing. 21044 2-4-C w/Teflon (92-850736A1) O-ring NOTE: Use thick 0.090 in. (2.29mm) washers (12-855941) under fasteners if not previously installed.
BIGFOOT GEAR HOUSING Water Pump Reassembly and Installation 1. Place upper seal on longer shoulder side of Oil Seal Driver (91-13949) with seal lip away from shoulder. 2. Apply Loctite 271 on O.D. of seal; press seal into water pump base until tool bottoms. 91-13949 51553 Loctite “271”...
Page 560
BIGFOOT GEAR HOUSING 3. Place lower seal on shorter shoulder side of Oil Seal Driver (91-13949) with seal lip to- ward shoulder. 4. Apply Loctite 271 on O.D. of seal; press seal into water pump base until tool bottoms. 5. Lubricate lip of each seal with Quicksilver 2-4-C w/Teflon (92-825407A12). 91-13949 51553 Loctite “271”...
Page 561
BIGFOOT GEAR HOUSING 7. Install components as shown. Apply Loctite 271 on bottom half of threads and torque to specified torque. 19217 Loctite “271” (92-809819) Water Pump Base Bolts and Washers Bolt Torque 60 lb-in. (6.8 Nm) 8. Install gasket and plate. 19219 Gasket Plate...
BIGFOOT GEAR HOUSING 10. Lubricate I.D. of cover with Quicksilver 2-4-C w/Teflon. 11. Rotate driveshaft clockwise and push cover down over impeller. 12. Install cover. 13. If water tube seal stayed on water tube (inside of driveshaft housing) when gear housing was removed, pull water tube seal from water tube.
BIGFOOT GEAR HOUSING 2. Pressurized housing to 10 to 12 psi (69-83 kPa) and observe gauge for 5 minutes. 3. Rotate driveshaft, prop shaft and move shift shaft while housing is pressurized to check for leaks. 4. If pressure drop is noted, immerse housing in water. 5.
Failure to follow this warning could result in acci- dental engine starting and possible injury. 1. Position outboard shift linkage into forward gear position. Models 40/50 Bigfoot (4-Stroke) Remote Control Model Shown Shift Lever Page 6B-58...
Page 565
BIGFOOT GEAR HOUSING Models 60 Bigfoot Shift Block Models 75/90/100/115/125 19879 Shift Block; Front of Block MUST Extend 1/8 in. (3.2 mm) Past Front of Rail. Rail 2. Tilt engine to full up position and engage tilt lock lever. 3. Shift gear housing into neutral position. Propeller shaft will rotate freely in either direc- tion.
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8. Install components as shown in appropriate photo. ALL EXCEPT 75 W/MECHANICAL REVERSE LOCK 53968 Nylon Spacer Shift Shaft Coupler Bushing 40/45/50 Bigfoot (4-Stroke) Only 75 W/MECHANICAL REVERSE LOCK 53925 Nylon Spacer Shift Shaft Coupler Flat; MUST BE Positioned Toward Front of Gear Housing...
Page 567
Fasteners and Washers (2 Each Side) Locknut and Washer Bolt or Nut Torque 40 lb-ft (54 Nm) 16. Check shift operation as follows: Place shift lever in forward gear. Gear housing should ratchet when propeller shaft is turned clockwise. Resistance should be felt when propeller shaft is turned counter- clockwise.
BIGFOOT GEAR HOUSING Trim Tab Adjustment 1. Check trim tab position as follows: Operate boat at the speed at which it normally would be operated. If the boat pulls to the right (STARBOARD), the trailing edge of trim tab must be moved to the right.
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THROTTLE LEVER BUSHING RETAINER SHIFT LEVER BRACKET NON HANDLE LATCH SCREW (M6 x 16) SLEEVE SHIFT ROD THROTTLE CAM THROTTLE CAM (40 ITALIAN) SPACER WASHER SCREW (M5 x 16) HORIZONTAL SHIFT SHAFT RETAINER WASHER COTTER PIN SPRING SPRING PLATE SCREW (M5 x 16)
THROTTLE/SHIFT LINKAGE Shift and Throttle Cable Installation To The Outboard Install the shift cable and throttle cable into the remote control and mount the remote control following instructions which are provided with the remote control. NOTE: Install the shift cable before the throttle cable. The shift cable is the first cable to move when the remote control handle is moved into gear.
THROTTLE/SHIFT LINKAGE Throttle Cable Installation NOTE: Attach Shift cable to engine prior to attaching throttle cable. 1. Position the remote control handle into neutral detent. 2. Fit the throttle cable thru the front rubber grommet and into the bottom cowl. 3.
Page 576
THROTTLE/SHIFT LINKAGE 5. Pull the throttle cable adjustment barrel out of the holder. 6. While holding down the throttle linkage arm (Step 4), position throttle lever so there is a 1/8 inch (3.2mm) gap between the top side of the oval shaped boss and top inside sur- face of the carburetor cam.
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TILLER HANDLE 3. Loosen the jam nuts and disconnect the throttle cables from the throttle lever. 54283 Throttle Cable (Long) Throttle Cable (Short) 4. Disconnect the tiller handle wiring. 5. Remove two screws securing the tiller handle. Remove the tiller handle assembly from the outboard.
TILLER HANDLE Tiller Handle Disassembly 1. Pry the two clips out of the hand grip. 2. Remove the side cover. Clips (2) Side Cover 3. Pull the arm along with the throttle cables and wiring from the bracket. 4. Remove retainer and slide out the tiller tube assembly. 5.
Page 583
TILLER HANDLE 6. Use a flat tip screwdriver to pry/push the rubber grip off the handle. 7. Pull out the stop switch harness. 8. Push the tiller tube out of the handle. Stop Switch Harness Tiller Tube Handle 9. Remove cover and disconnect throttle cables from pulley. Cover Throttle Cables Pulley...
Tiller Handle Reassembly 1. Wrap cables around pulley as shown. Short Throttle Cable (30-1/2 in.) Place in Top Groove Long Throttle Cable (40-1/2 in.) Place in Bottom Groove Pulley 2. Place pulley and cables into case. 3. Install cover with screw.
Page 585
TILLER HANDLE 4. Match tiller tube end with the slots and pull the tube end into the handle until it bottoms out. 5. Install the throttle lock components on tiller tube. Tiller Tube Handle Match the Tube End with Slots Screw Lock Spring...
Page 586
TILLER HANDLE 9. Place pulley assembly into arm. 10. Slide the tiller tube into the arm. Position the throttle lock knob into its slot. 11. Match the end of the tiller tube with the slots in the pulley assembly. Insert the tiller tube end into the pulley assembly.
Page 587
TILLER HANDLE 15. Pull the throttle cables and wiring into the bracket. 16. Fasten arm with cover. Arm Cover Screw Torque 135 lb-in. (15.3 Nm) CAUTION Wiring passing through the hand grip opening must be protected from chaffing or being cut, by using the wiring conduit described in the following steps. Failure to protect wiring as described could result in electrical system failure.
TILLER HANDLE Tiller Handle Installation 1. Install diaphragm to the cable bracket. Refer to Section 2C for adjustment after tiller han- dle is installed. 2. Install cable bracket. 54281 Diaphragm Cable Bracket Screws (2) Cable Bracket Screw Torque 75 lb-in. (8.5 Nm) CAUTION Tiller handle outboard must have the reinforced throttle lever.
Page 589
TILLER HANDLE 3. If removed, install hardware to the throttle lever as shown. 45 HP Models 50 HP Models Screw Bushing 4. Install throttle lever. 2-4-C w/Teflon (92-850736A1) Bushing (Existing) Screw (Existing) Throttle Lever Screw Torque 100 lb-in. (11.3 Nm) 90-828631R3 MARCH 1999 Page 7B-13...
Page 590
TILLER HANDLE 5. 50 HP Models – adjust screw to allow for some free play in the carburetor linkage at wide open throttle. Do not allow the carburetor shutters to act as throttle stops. NOTE: 45 HP Models – the throttle stop is fixed and does not require adjustment. 54281 6.
Page 591
TILLER HANDLE b. S/N 0G472133 and up. 54277 Switch Assembly Backing Plate Screw (2) BIGFOOT 56243 Switch Backing Plate Screws (2)-Fully Tighten 90-828631R3 MARCH 1999 Page 7B-15...
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TILLER HANDLE 7. Install tiller handle assembly. 8. Pry up the left side lower corner of the rubber grommet in order to fit the wiring in the lower opening. 9. Connect the auxiliary harness. Refer to wiring diagram on next page. 10.
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TILLER HANDLE 11. Reconnect wires. YEL/RED BLK/YEL BLK/YEL BLK/YEL BLK/YEL YEL/RED TAN/BLU BLK = Black BLU = Blue GRY = Gray GRN = Green PUR = Purple RED = Red TAN = Tan YEL = Yellow 12. Connect wiring harness into the engine wiring harness. Push the harness connection into the holder.
Page 594
TILLER HANDLE 13. Rotate throttle grip to idle position. 14. Insert the anchor on the shorter throttle cable into the anchor hole on the throttle lever. Push in the anchor until it bottoms out. Cable has to be aligned with the slot. 54282 Shorter Throttle Cable Cable Must be able to Rotate in Slot...
Page 595
TILLER HANDLE 16. Route the longer throttle cable behind the cable bracket as shown. 17. Insert the anchor into the anchor hole on the throttle cable. 18. Place the throttle cable into the notch in the cable bracket. 54284 Longer Throttle Cable (Position Behind Cable Bracket as Shown) Cable Must be able to Rotate in Slot 19.
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TILLER HANDLE c. While holding down the throttle linkage arm (Step b), adjust the throttle cable jam nuts so there is a 1/8 in. (3.2mm) gap between the top side of the oval shaped boss and top inside surface of the throttle cam. With the throttle lever at this position, tight- en the jam nuts.
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TILLER HANDLE NON-BIGFOOT s/n 0G472133 and above s/n 0G472132 and below Cotter Pin Washer Shift Rod BIGFOOT 56249 Shift Rod Assembly Shift Link Washer Cotter Pin 90-828631R3 MARCH 1999 Page 7B-21...
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TILLER HANDLE 21. Attach swivel linkage to shift rod. Attach swivel/rod assembly to shift link. Make sure threads are fully engaged but do not tighten completely. 22. Secure bracket and shift rod assembly to side of powerhead with bolts. Torque bolts to specified torque.
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TILLER HANDLE 24. Assemble the shift rod into the shift handle. 54286 Shift Rod Shift Handle 25. Secure the shift handle as shown. 2-4-C w/Teflon (92-850736A1) Shift Handle Bushing Screw Screw Torque 100 lb-in. (11.3 Nm) 90-828631R3 MARCH 1999 Page 7B-23...
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