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FOREWORD GROUP INDEX This manual contains an introductory description on the SUZUKI Outboard motor DF2.5 and procedures for its inspection, service and overhaul of its main GENERAL INFORMATION components. Other information considered as generally known is not included. PERIODIC MAINTENANCE...
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HOW TO USE THIS MANUAL TO LOCATE WHAT YOU ARE LOOKING FOR: 1. The text of this manual is divided into sections. 2. The section titles are listed in the GROUP INDEX. 3. Holding the manual as shown at the right will allow you to find the first page of the section easily.
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Apply oil. Use the engine oil unless Apply THREAD LOCK “1342”. otherwise specified. Apply SUZUKI OUTBOARD MOTOR Measure in resistance range. GEAR OIL. Apply SUZUKI SUPER GREASE “A”. Measure in continuity test range. Apply SUZUKI WATER RESISTANT Use special tool. GREASE. Apply SUZUKI BOND “1207B”.
1-2 GENERAL INFORMATION WARNING / CAUTION / NOTE Please read this manual and follow its instructions carefully. To emphasize special information, the symbol and the words WARNING, CAUTION and NOTE have special meanings. Pay special attention to the mes- sages highlighted by these signal words. ...
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GENERAL INFORMATION 1-3 • If parts replacement is necessary, replace the parts with Suzuki Genuine Parts or their equiv- alent. • When removing parts that are to be reused, keep them arranged in an orderly manner so that they may be reinstalled in the proper order and orientation.
FUEL AND OIL GASOLINE RECOMMENDATION Suzuki highly recommends that you use alcohol-free unleaded gasoline with a minimum pump octane rating of 87 (R/2 + M/2 method) or 91 (Research method). However, blends of unleaded gasoline and alcohol with equivalent octane content may be used.
GENERAL INFORMATION 1-5 ENGINE OIL Use only oils that are rated SE, SF, SG, SH or SJ under the API (American Petroleum Institute) classification system. The viscosity rating should be SAE 10W-40. If an SAE 10W-40 motor oil is not available, select an alternative according to the chart at right.
1-6 GENERAL INFORMATION ENGINE BREAK-IN The first 10 hours are critically important to ensure correct run- ning of either a brand new motor or a motor that has been recon- ditioned or rebuilt. How the motor is operated during this time will have direct bearing on its life span and long-term durability.
GENERAL INFORMATION 1-7 PROPELLERS An outboard motor is designed to develop its rated power within a specified engine speed range. The maximum rated power delivered by the DF2.5 models are shown below. Recommended operating 5 250 – 5 750 r/min range If the standard propeller fails to meet the above requirement, use another pitch propeller to hold the engine speed within the...
1-8 GENERAL INFORMATION * SPECIFICATIONS * These specifications are subject to change without notice. Data Item Unit DF2.5 PRE-FIX 00251F DIMENSIONS & WEIGHT Overall length mm (in) 437 (17.2): with tiller handle raised (front to back) Overall width mm (in) 262 (10.3) (side to side) Overall height...
1-10 GENERAL INFORMATION * SERVICE DATA * These service data are subject to change without notice. Data Item Unit DF2.5 POWER HEAD Recommended operating r/min 5 250 – 5 750 range Idle speed r/min 1 900 ± 100 (in-gear: approx. 1 500) * Cylinder compression 960 –...
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GENERAL INFORMATION 1-11 Data Item Unit DF2.5 VALVE/VALVE GUIDE Valve diameter mm (in) 20.0 (0.79) mm (in) 18.0 (0.71) Valve mm (in) 0.13 – 0.17 (0.005 – 0.007) clearance (Cold engine EX STD mm (in) 0.13 – 0.17 (0.005 – 0.007) condition) Valve seat angle —...
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1-12 GENERAL INFORMATION Data Item Unit DF2.5 CYLINDER/PISTON/PISTON RING Cylinder distortion Limit mm (in) 0.05 (0.002) Piston to cylinder mm (in) 0.018 – 0.033 (0.0007 – 0.0013) clearance Limit mm (in) 0.100 (0.0039) Cylinder bore mm (in) 48.000 – 48.015 (1.8898 – 1.8904) Cylinder measuring mm (in) 20 (0.8) from cylinder top surface...
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GENERAL INFORMATION 1-13 Data Item Unit DF2.5 CRANKSHAFT/CONROD Conrod small end mm (in) 12.006 – 12.014 (0.4727 – 0.4730) inside diameter Limit mm (in) 12.040 (0.4740) Conrod big end mm (in) 0.015 – 0.035 (0.0006 – 0.0014) oil clearance Limit mm (in) 0.080 (0.0031) Conrod big end...
1-14 GENERAL INFORMATION TIGHTENING TORQUE Tightening torque – Important fasteners THREAD TIGHTENING TORQUE ITEM DIAMETER N·m kg-m lb-ft Cylinder head cover bolt 5 mm Cylinder head bolt 6 mm Crankcase bolt 6 mm Conrod cap bolt 5 mm Valve adjusting lock nut 5 mm Intake pipe bolt 6 mm...
GENERAL INFORMATION 1-17 MATERIALS REQUIRED SUZUKI OUTBOARD SUZUKI WATER RESIS- SUZUKI SILICONE SEAL SUZUKI BOND “1207B” MOTOR GEAR OIL TANT GREASE *99104-33140 99000-22540 99000-25161 99000-31120 99000-31140 (400 ml × 24 pcs.) (250 g) (50 g) (100 g) THREAD LOCK “1342”...
2-2 PERIODIC MAINTENANCE PERIODIC MAINTENANCE SCHEDULE The chart below lists the recommended intervals for all the required periodic service work necessary to keep the motor operating at peak performance and economy. Maintenance intervals should be judged by number of hours or months, whichever comes first. NOTE: More frequent servicing should be performed on outboard motors that are used under severe conditions.
PERIODIC MAINTENANCE 2-3 MAINTENANCE AND TUNE-UP PROCEDURES This section describes the servicing procedures for each of the periodic maintenance requirements. ENGINE OIL ENGINE OIL LEVEL CHECK Inspect the oil level before every use. 1. Place the motor in a vertical position. 2.
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2-4 PERIODIC MAINTENANCE ENGINE OIL CHANGE Change initially after 20 hours (1 month) and every 100 hours (6 months) thereafter. NOTE: Change the engine oil while the engine is warm. 1. Place the motor in a vertical position and remove the motor cover.
Gear oil amounts: 60 ml (2.0/2.1 US/Imp. oz) Recommended oil: SUZUKI OUTBOARD MOTOR GEAR OIL or SAE #90 HYPOID GEAR OIL 5. Install the oil level plug before removing the oil filler tube from the drain hole.
2-6 PERIODIC MAINTENANCE LUBRICATION Inspect every 50 hours (3 months). Apply the Water Resistant Grease to the following points. 99000-25161: SUZUKI WATER RESISTANT GREASE Throttle cable Swivel bracket Clamp screw Propeller shaft...
PERIODIC MAINTENANCE 2-7 SPARK PLUG • Inspect every 100 hours (6 months). • Replace every 200 hours (12 months). Standard spark plug: NGK CR6HSA Only resistor (R) type spark plugs must be used with this engine. Using a non-resistor spark plug will cause ignition system malfunctions.
2-8 PERIODIC MAINTENANCE VALVE CLEARANCE Inspect initially after 20 hours (1 month) and every 200 hours (12 months) thereafter. CHECKING 1. Remove the following parts: • Motor cover (See page 5-2) • Recoil starter (See page 5-2) • Spark plug 2.
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PERIODIC MAINTENANCE 2-9 Valve clearance 4. Measure the valve clearance by inserting thickness gauge between the valve stem end and the rocker arm. 09900-20803: Thickness gauge Valve clearance (cold engine condition): IN. & EX. 0.13 – 0.17 mm (0.005 – 0.007 in) If the valve clearance is out of the specification, adjust the clear- ance.
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2-10 PERIODIC MAINTENANCE INSTALLATION Installation is reverse order of removal with the special attention to the following steps. • Tighten the four cylinder head cover bolts diagonally to the specified torque. Cylinder head cover bolt: 7 N·m (0.7 kg-m, 5.0 lb-ft) ...
PERIODIC MAINTENANCE 2-11 IDLE SPEED Inspect initially after 20 hours (1 month) and every 200 hours (12 months) thereafter. CHECKING 1. Check the link mechanism and the carburetor throttle valves for smooth operation. 2. Remove the motor cover. 3. Tie a knot in the rope inside of the motor cover, in order to prevent the rope binding onto the recoil reel when the starter grip is off.
2-12 PERIODIC MAINTENANCE ADJUSTMENT If engine idle speed is out of specification, adjust engine speed. Turn the idle adjustment screw A clockwise to increase idle speed or counterclockwise to decrease idle speed. CARBURETOR Inspect initially after 20 hours (1 month) and every 100 hours (6 months) thereafter.
PERIODIC MAINTENANCE 2-13 BREATHER HOSE AND FUEL LINE • Inspect initially after 20 hours (1 month) and every 50 hours (3 months) thereafter. • Replace every 2 years. If leakage, crack, swelling or other damage is found, replace the breather hose and/or the fuel line. FUEL FILTER Replace every 400 hours or 2 years.
ANODE Inspect every 50 hours (3 months). If 2/3 of the anode has corroded away, replace the anode. Anode Do not paint the anode. NOTE: Apply the silicone seal to the anode securing bolts. 99000-31120: SUZUKI SILICONE SEAL...
PERIODIC MAINTENANCE 2-15 BOLTS AND NUTS Inspect initially after 20 hours (1 month) and every 100 hours (6 months) thereafter. Check that all bolts and nuts listed below are tightened to the each specified torque. THREAD TIGHTENING TORQUE ITEM DIAMETER N·m kgf-m lb-ft...
2-16 PERIODIC MAINTENANCE CYLINDER COMPRESSION NOTE: Figures shown are guidelines only, not absolute service limits. Cylinder compression: 960 – 1 400 kPa (9.6 – 14.0 kg/cm , 137 – 199 psi) Low compression pressure can indicate one or more of the fol- lowing: •...
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IGNITION AND ELECTRICAL 3-1 IGNITION AND ELECTRICAL CONTENTS IGNITION SYSTEM..................3- 2 OUTLINE ....................3- 2 IGNITION TROUBLESHOOTING ............3- 4 INSPECTION ...................3- 5 REMOVAL AND INSTALLATION............3- 7...
3-2 IGNITION AND ELECTRICAL IGNITION SYSTEM OUTLINE A transistorized ignition system is employed on the DF2.5. This system consists of flywheel magneto, igniter unit, spark plug and emergency/engine stop switch. Flywheel magneto Igniter unit Spark plug Emergency/engine stop switch SPECIFICATIONS Ignition type Transistorized ignition Ignition timing...
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IGNITION AND ELECTRICAL 3-3 OPERATION The transistorized ignition circuit will be discussed by referring to the diagram below: When the recoil starter is pulled, the flywheel is turned. An electromotive force generated in the primary winding (n ) of the ignition coil makes the transistor (TR ) conduct through the resistor (R ) and forms the pri- mary circuit (indicated by dashed lines).
3-4 IGNITION AND ELECTRICAL IGNITION TROUBLESHOOTING Perform the following ignition system tests when the engine is hard to start in order to determine if the cause is in the ignition or another system. START The cause will not be in the ignition system.
IGNITION AND ELECTRICAL 3-5 INSPECTION IGNITER Measure the resistance in the igniter unit. 09930-99320: Digital tester Tester range: Ω (Resistance) 1. Remove the spark plug cap from the high-tension cord. 2. Measure the resistance. Primary coil Tester probe connection Probe Other probe Primary coil...
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3-6 IGNITION AND ELECTRICAL EMERGENCY / ENGINE STOP SWITCH 1. Lock plate 09930-99320: Digital tester 2. Button Tester range: (Continuity) Inspect the continuity of the emergency/engine stop switch. Tester probe connection Probe Other probe Black Black Emergency/engine stop switch continuity: Continuity Switch condition Lock plate IN...
IGNITION AND ELECTRICAL 3-7 REMOVAL AND INSTALLATION Nut (1) Starter pulley (1) 10 N·m (1.0 kg-m, 7.0 lb-ft) " Flywheel magneto (1) Key (1) Bolt (2) Igniter unit (1) Spark plug cap (1) 45 N·m 4.5 kg-m 32.5 lb-ft Crankshaft NOTE: Clean the flywheel and crankshaft mating surfaces with cleaning solvent.
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3-8 IGNITION AND ELECTRICAL 5. Remove the flywheel from the crankshaft using the proper marketing tool. 6. Remove the key from the crankshaft. INSTALLATION Installation is reverse order of removal with the special attention to the following steps. Flywheel magneto •...
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FUEL SYSTEM 4-1 FUEL SYSTEM CONTENTS PRECAUTION ON FUEL SYSTEM SERVICE ..........4- 2 GENERAL PRECAUTION...............4- 2 FUEL LINE .....................4- 2 REMOVAL AND INSTALLATION............4- 2 CARBURETORS ...................4- 5 REMOVAL AND INSTALLATION............4- 5 DISASSEMBLY ..................4- 7 CLEANING AND INSPECTION ..............4-10 REASSEMBLY ..................4-11 FUEL TANK AND FUEL COCK ..............4-13 REMOVAL ....................4-13 INSPECTION ...................4-14...
4-2 FUEL SYSTEM PRECAUTION ON FUEL SYSTEM SERVICE GENERAL PRECAUTION Gasoline is extremely flammable and toxic. Always observe the following precautions when working around gasoline or servicing the fuel system. • Keep the working area well ventilated and away from open flame (such as gas heater) or sparks.
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FUEL SYSTEM 4-3 REMOVAL 1. Remove the motor cover. 2. Remove the recoil starter. 3. Turn the fuel cock lever “OFF” position. 4. Loosen the screw 1 securing the throttle control inner cable. 5. Detach the choke rod 2 from the carburetor. 6.
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4-4 FUEL SYSTEM INSTALLATION Installation is reverse order of removal with the special attention to the following steps. Do not re-use the removed gasket. Always use a new gasket. • Tighten the carburetor mounting bolts to the specified torque. ...
FUEL SYSTEM 4-5 CARBURETORS Before servicing the fuel system, read and understand “PRECAUTION ON FUEL SYSTEM SERVICE” in the previous section. REMOVAL AND INSTALLATION REMOVAL 1. Remove the motor cover. 2. Remove the recoil starter. 3. Turn the fuel cock “OFF” position. 4.
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4-6 FUEL SYSTEM INSTALLATION Installation is reverse order of removal with the special attention to the following steps. Do not re-use the removed gasket. Always use a new gasket. • Tighten the carburetor mounting bolts to the specified torque. ...
FUEL SYSTEM 4-7 DISASSEMBLY Idle adjusting screw (1) Screw (4) Plate (1) Main air jet (1) Pilot air jet (1) Screw (1) Pilot jet (1) Bolt (1) Float chamber (1) Float pin (1) Float (1) Float spring (1) Needle valve (1) Main jet (1) Main nozzle (1) Gasket (1)
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4-8 FUEL SYSTEM 3. Remove the main air jet 4, the pilot air jet 5 and the screw 4. Remove the pilot jet 7. 5. Remove the bolt 8 and the float chamber 9. 6. Remove the float pin 0, the float A and the float spring B. ...
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FUEL SYSTEM 4-9 7. Remove the needle valve C from the float. 8. Remove the main jet D. 9. Remove the main nozzle E.
4-10 FUEL SYSTEM CLEANING AND INSPECTION Clean thoroughly with cleaning solvent and compressed air before inspection. Wear safety glasses when using compressed air to expel solvent, carburetor cleaner etc. Do not place any rubber, plastic and non-metallic parts in cleaning solvent, as severe damage or deteri- oration will result.
FUEL SYSTEM 4-11 FLOAT Inspect the float. If crack or other damage is found, replace the float. REASSEMBLY Reassembly is reverse order of disassembly with the special attention to the following steps. MAIN JET AND MAIN NOZZLE Install the main nozzle 1 to the carburetor body before installing the main jet 2.
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4-12 FUEL SYSTEM 3. Install the float pin spring 4. NOTE: After installing float, inspect for smooth movement of float. CHECKING FLOAT HEIGHT Measure the float height. NOTE: Make sure that float weight is not applied to needle valve. 09900-20101: Vernier calipers Float height H: 10 ±...
FUEL SYSTEM 4-13 FUEL TANK AND FUEL COCK REMOVAL 1. Remove the motor cover. 2. Remove the recoil starter 1. (See page 5-2.) 3. Turn the fuel cock lever 2 “OFF” position. 4. Remove the fuel hose 3 from the fuel cock 4. 5.
4-14 FUEL SYSTEM INSPECTION Fuel cock Check the filter. If clogged or damaged is found, clean the filter or replace the fuel cock assy. Inspect the fuel cock. If leakage, deterioration or other damage is found, replace the fuel cock assy. Fuel tank Inspect the fuel tank.
5-2 RECOIL STARTER REMOVAL 1. Remove the motor cover. 2. Tie a knot in the rope inside of the motor cover to prevent the rope from rewinding onto the recoil reel when the starter grip is removed. 3. Remove the knot from grip holder 1. Remove the grip holder 1 and the starter grip 2.
RECOIL STARTER 5-3 DISASSEMBLY Because of the coiled tension in the recoil spring, wear safety glasses and hand protection when wind- ing or unwinding the component. Rope (1) Reel (1) " Screw (1) Friction plate (1) Spring (1) Ratchet (1) &...
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5-4 RECOIL STARTER 1. Turn the reel 1 clockwise in order to release the coiled ten- sion in the recoil spring. 2. Remove the screw 2 and the friction plate 3. NOTE: Screw 2 is a left hand thread. 3. Remove the spring 4 and the ratchet 5. 4.
RECOIL STARTER 5-5 6. Remove the rope 7 from the reel 1. INSPECTION NOTE: If excessive wear, crack, defective or other damage is found on any component, replace. • Inspect the ratchet and the all springs. If excessive wear or other damage is found, replace. •...
• Apply the Water Resistant Grease to the recoil spring. 99000-25161: SUZUKI WATER RESISTANT GREASE • Install the rope 7. • Install the reel 1 and the recoil spring to the recoil case align- ing the inner end of the spring with the boss cutaway on the case.
RECOIL STARTER 5-7 • Install the friction plate 3. • Apply THREAD LOCK “1342” to threads of screw 2 then tighten the screw 2. NOTE: Screw 2 is a left hand thread. 99000-32050: THREAD LOCK “1342” • Rotate the reel approximately 4 turns counterclockwise until the recoil spring is tensioned.
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POWER UNIT 6-1 POWER UNIT CONTENTS POWER UNIT ....................6- 2 REMOVAL ....................6- 2 INSTALLATION..................6- 4 CYLINDER HEAD / VALVE / ROCKER ARM ..........6- 7 REMOVAL ....................6- 7 INSTALLATION..................6- 8 DISASSEMBLY ..................6-10 INSPECTION AND SERVICING .............6-11 REASSEMBLY ..................6-17 CYLINDER / PISTON / CRANKSHAFT / CONROD / CAMSHAFT....6-18 DISASSEMBLY ..................6-18 INSPECTION AND SERVICING .............6-22 REASSEMBLY ..................6-31...
6-2 POWER UNIT POWER UNIT REMOVAL Before removing the power unit: • Drain the engine oil. (See page 2-4.) • Shift into “NEUTRAL” position. 1. Remove the recoil starter assy 1. (See page 5-2.) 2. Remove the fuel tank 2. (See page 4-13.) 3.
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POWER UNIT 6-3 7. Remove the four engine mounting bolts. 8. Detach the power unit with the lower cover. 9. Remove the four bolts, then detach the power unit from the lower cover. 10. Remove a bolt 7 and oil seal protector 8.
Do not re-use the gasket once removed. Always use new parts. 2. Apply the Water Resistant Grease to the driveshaft splines. 99000-25161: SUZUKI WATER RESISTANT GREASE 3. Apply the Water Resistant Grease to the seal lips of the driveshaft oil seal.
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7. Apply the Silicone Seal to the four power unit mounting bolts and tighten the bolts to the specified torque. 99000-31120: SUZUKI SILICONE SEAL Power unit mounting bolt: 10 N·m (1.0 kg-m, 7.0 lb-ft) FLYWHEEL MAGNETO •...
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6-6 POWER UNIT FINAL ASSEMBLY CHECK Perform the following checks in order to ensure proper and safe operation of the repaired unit. • All parts removed have been returned to the original posi- tions. • Lower unit gear engagement is properly adjusted. (See page 8-19.) •...
POWER UNIT 6-7 CYLINDER HEAD / VALVE / ROCKER ARM REMOVAL 1. Remove the two bolts, the intake manifold 1 and the insula- tor 2. 2. Remove the four bolts 3 and the cylinder head cover 4. 3. Remove the valve adjusting lock nuts 5, then remove the valve adjusting screw 6.
1. Before installing cylinder head gasket, apply bond to both surfaces of the hatched areas shown in illustration. 99000-31140: SUZUKI BOND “1207B” 2. Insert the dowel pins 1 and place a new cylinder head gas- ket 2 into position on cylinder.
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POWER UNIT 6-9 6. Install the two push rods 3 onto the cam rocker arms 4. 7. Install the rocker arms 5 and the rocker arm shaft 6. 8. Adjust the valve clearance. (See page 2-8 and 2-9.) 9. Install the cylinder head cover and the gasket, then tighten the four cylinder head cover bolts diagonally to the specified torque.
6-10 POWER UNIT DISASSEMBLY 1. Remove the retainer 1. NOTE: To remove the retainer, push it with the thumbs of both hands: move it in the arrow direction and force it off the valve shaft. 2. Remove the valve springs 2. NOTE: Reassemble each valve spring to their original position.
POWER UNIT 6-11 INSPECTION AND SERVICING NOTE: If excessive wear, crack, defective or other damage is found on any component, replace. CYLINDER HEAD 1. Remove all carbon from the combustion chamber. NOTE: • Do not use any sharp edged tool in order to scrape carbon off the cylinder head or the head components.
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6-12 POWER UNIT Water jacket Inspect the water jackets for clog or obstruction. Clean the water jackets if necessary. ROCKER ARM AND ROCKER ARM SHAFT Inspect the rocker arm for wear, crack or other damage. Replace it necessary. Inspect the rocker arm shaft for wear, bend or other damage. Replace it necessary.
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POWER UNIT 6-13 VALVE/VALVE GUIDE Using the micrometer and a small bore gauge, take the diameter readings on the valve stems and the guides in order to check the guide to stem clearance. Be sure to take readings at more than one place along length of each stem and guide.
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6-14 POWER UNIT Valve stem end Inspect the valve stem end face for pitting and wear. If pitting or wear is found, the valve stem end may be resurfaced. If the chamfer of stem end has been worn away, replace the valve.
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POWER UNIT 6-15 Valve seat contact width Measure the valve seat contact width as follows. 1. Remove all carbon from the valve and seat. 2. Coat the valve seat evenly with Prussian Blue (or equiva- lent). 3. Install the valve into the valve guide. 4.
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6-16 POWER UNIT VALVE SPRING Valve spring free length Measure the valve spring free length. 09900-20101: Vernier calipers Valve spring free length: Standard: IN. & EX. 22.42 mm (0.883 in) Service limit: IN. & EX. 21.52 mm (0.847 in) If the measurement exceeds the service limit, replace the valve spring.
POWER UNIT 6-17 REASSEMBLY Reassembly is reverse order of disassembly with the special attention to the following steps. 1. Apply engine oil to the valve stem seals 1. 2. Install the valve stem seals to the valve guide. Do not re-use the removed valve stem seal. Always use a new stem seal.
6-18 POWER UNIT CYLINDER / PISTON / CRANKSHAFT / CONROD / CAMSHAFT DISASSEMBLY 1. Remove the power unit. (See page 6-2.) 2. Remove the cylinder head. (See page 6-7.) 3. Remove the bolt 1 and the under oil seal plate 2. 4.
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POWER UNIT 6-19 7. Remove the oil pump shaft A, camshaft B and shaft C. 8. Remove the two conrod bolts D and the conrod cap E. 9. Remove the piston with the conrod through the top of the cylinder bore. 10.
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6-20 POWER UNIT 12. Remove the screw L and the oil pump outer plate M. 13. Remove the inner rotor N and the outer rotor O. 14. Remove the four bolts and the thermostat cover P. 15. Remove the thermostat Q. 16.
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POWER UNIT 6-21 17. Remove a screw S and the reed valve T.
6-22 POWER UNIT INSPECTION AND SERVICING NOTE: If excessive wear, crack, defective or other damage is found on any component, replace. CAMSHAFT Cam face Inspect the cam face for scratches and wear. Cam wear Measure the cam height H. 09900-20202: Micrometer Cam height: Standard: IN.
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POWER UNIT 6-23 CYLINDER / PISTON / PISTON RING Cylinder distortion Using a straightedge and the thickness gauge, measure the gasket surface of the cylinder at a total of six locations as shown in the figure. 09900-20803: Thickness gauge Cylinder distortion: Service limit: 0.05 mm (0.002 in) If the measurement exceeds the service limit, resurface or...
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6-24 POWER UNIT Piston to cylinder clearance To check the clearance, measure the following items. • Cylinder bore at 20 mm elevation from the gasket surface at a 20 mm right angle to the crankshaft pin. • Piston skirt diameter at 5 mm elevation from the skirt end. ...
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POWER UNIT 6-25 Piston ring to groove clearance Before checking, the piston grooves must be clean, dry and free Piston ring of carbon. Fit the piston ring into the piston groove, and measure the clear- ance between the ring and the ring groove using the thickness gauge.
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6-26 POWER UNIT Piston ring free end gap Measure the piston ring free end gap. 09900-20101: Vernier calipers Piston ring free end gap: Standard: Approx. 6.1 mm (0.24 in) 2nd Approx. 5.7 mm (0.22 in) Service limit: 4.9 mm (0.19 in) 2nd 4.6 mm (0.18 in) If the measurement exceeds the service limits, replace the pis- ton ring.
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POWER UNIT 6-27 Conrod big end side clearance Measure the clearance with the conrod installed on the crank pin as shown in the figure. 09900-20803: Thickness gauge Conrod big end side clearance: Standard: 0.20 – 0.70 mm (0.008 – 0.028 in) Service limit: 1.00 mm (0.039 in) If the measurement exceeds the service limit, replace the con- rod assembly and/or crankshaft.
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6-28 POWER UNIT Conrod big end oil clearance Check the clearance as follows. 1. Clean the surface of the conrod, the conrod cap and the crank pin. 2. Place a piece of the plastigauge on the crank pin parallel to the crankshaft, avoiding the oil hole.
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POWER UNIT 6-29 OIL SEAL AND BEARING Visually check the oil seals installed in the cylinder block and crankcase for cut, nick, excessive wear or other damage. Visually check the crankshaft upper bearing for pitting, noisy, rough or other damage. NOTE: If neither defective nor any damage is found on the oil seals and the bearing, do not remove the oil seals and the bearing.
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6-30 POWER UNIT OIL PUMP Inspect the outer rotor, the inner rotor and the rotor plate for excessive wear or other damage. Replace it necessary.
POWER UNIT 6-31 REASSEMBLY Reassembly is reverse order of disassembly with the special attention to the following steps. • If the original components are not replaced, each piston, piston pin and conrod is to be assembled and installed in the original order and position. •...
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6-32 POWER UNIT PISTON RING TO PISTON Oil ring 1. Apply engine oil to the piston rings. 2. Install the spacer 1 first, then the side rails 2 to the piston. When installing the spacer, do not allow the ends to Incorrect overlap in the groove.
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2. Apply the Water Resistant Grease to the lip of the upper oil seal. 09900-25161: SUZUKI WATER RESISTANT GREASE 3. Install the crankshaft 1 to the cylinder block. 4. Apply engine oil to the piston and the cylinder wall.
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6-34 POWER UNIT CONROD CAP 1. Apply engine oil to the crank pin, the connecting rod and the connecting rod cap 1. 2. Install the conrod cap in the direction as shown in the figure. Slit mark 3. Apply engine oil lightly to the conrod bolts. 4.
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POWER UNIT 6-35 CAM ROCKER ARM 1. Apply engine oil to the cam rocker arm shaft 1. 2. Install the washer 2 and the spring 3 to the shaft 1 as shown in the figure. 3. Install the cam rocker arm 4, the washer 5 and the cam rocker arm 6.
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6-36 POWER UNIT 6. Install the oil pump shaft 5. CRANKCASE TO CYLINDER 1. Clean the mating surfaces of the cylinder block and the crankcase. 2. Install the two dowel pins 1 and the gasket 2 to the cylinder block. 3.
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3. Install the thermostat 3. 4. Apply sealant to both surfaces of thermostat cover gasket (as shown with hatched lines). 99000-31120: SUZUKI SILICONE SEAL 5. Install the gasket and the thermostat cover 4 to the cylinder block and secure with the four bolts.
2. Apply sealant to both surfaces of thermostat cover gasket (as shown with hatched lines). 99000-31120: SUZUKI SILICONE SEAL 3. Install the gasket 2 and the thermostat cover 3 to the cylin- der block and secure with the four bolts 4.
POWER UNIT 6-39 OPERATION WATER COOLING SYSTEM The water cooling system consists of the water pump (in the lower unit), the water tube (between the lower unit and the power unit) and the thermostat (in the cylinder). This system cools both the power unit and the exhaust and is shown in schematic form below.
6-40 POWER UNIT ENGINE LUBRICATION SYSTEM A camshaft driven trochoid type pump provides engine oil to all power unit components requiring lubrication. ENGINE OIL LUBRICATION CHART Crankshaft upper bearing Cylinder head Valve train Cylinder block · Connecting rod · Piston ·...
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7-2 MID UNIT DRIVESHAFT HOUSING/SWIVEL BRACKET/CLAMP BRACKET DISASSEMBLY Remove the power unit. (See page 6-2.) Remove the lower unit. (See page 8-2.) Remove the water tube 1 with the grommet upside. Remove the spring pin 3 and the tilt lock wing nut 4. Remove the tilt lock spacer 5.
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MID UNIT 7-3 Remove the tilt lock bolt 2 and the thrust block with the lower thrust mount 0. Remove the starboard side clamp bracket A, the tilt friction washer B and the swivel shaft bolt C. Remove the two swivel bracket bolts D. Remove the port side swivel bracket E.
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7-4 MID UNIT Remove the stopper bracket H. Remove the starboard side swivel bracket I. Take out the steering upper bush J from the driveshaft housing...
MID UNIT 7-5 INSPECTION NOTE: If excessive wear, crack, defective or other damage is found on any component, replace. DRIVESHAFT HOUSING If crack or other damage is found, replace. CLAMP BRACKET/SWIVEL BRACKET Inspect the clamp brackets and swivel bracket. If crack or other damage is found, replace. STEERING UPPER BUSHING Inspect the upper bushings.
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7-6 MID UNIT SWIVEL SHAFT BOLT Inspect the swivel shaft bolt. If wear, twist, bend or other damage is found, replace. WATER TUBE Inspect the water tube. If clog, obstruction or other damage is found, clean or replace.
MID UNIT 7-7 REASSEMBLY Reassembly is reverse order of disassembly with the special attention to the following steps. Consisting parts 8 N . m 0.8 kg-m 6.0 lb-ft 10 N . m 1.0 kg-m 7.0 lb-ft 8 N . m 0.8 kg-m 6.0 lb-ft 10 N .
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DRIVESHAFT HOUSING/SWIVEL BRACKET After completing reassembly of the mid unit, apply the Water Resistant Grease through grease nipple. 99000-25161: SUZUKI WATER RESISTANT GREASE • Apply the Water Resistant Grease to the following parts. - Inside and outside surfaces of the bushings.
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• Install the clamp bracket starboard side 1, the tilt friction washer 2 and the swivel shaft bolt 3. 99000-25161: SUZUKI WATER RESISTANT GREASE • Install the thrust block 5 with the lower thrust mount and the tilt lock bolt 4.
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7-10 MID UNIT LUBRICATION After completing reassembly of the mid unit, apply the Water Resistant Grease through grease nipple. 99000-25161: SUZUKI WATER RESISTANT GREASE...
MID UNIT 7-11 TILLER HANDLE REMOVAL • Remove the three bolts and the recoil starter. • Remove the throttle cable 1 from the carburetor. • Loosen the lock nuts 2 and remove the throttle cable 1 from the throttle cable holder 3. •...
7-12 MID UNIT • Remove the two tiller handle bushings A, the tiller handle mount C and the tiller handle spacer B from the tiller handle. DISASSEMBLY/REASSEMBLY DISASSEMBLY • Remove the throttle adjust knob 1. • Remove the throttle cable screw 3 and the cable stopper 2. •...
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(1.7 kg-m, 12.5 lb-ft) • Apply the Water Resistant Grease to the throttle handle mount 1. 99000-25161: SUZUKI WATER RESISTANT GREASE • Install the throttle handle mount 1 in position. • Install the throttle handle spacer 3 and the throttle handle...
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7-14 MID UNIT • Install the tiller handle washers 4 and the handle pivot bolt • Apply the Thread Lock to the handle pivot bolt. 99000-32050: THREAD LOCK “1342” • Tighten the tiller handle pivot bolt 5 to the specified torque. ...
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LOWER UNIT 8-1 LOWER UNIT CONTENTS REMOVAL AND DISASSEMBLY..............8- 2 INSPECTION ....................8- 6 REASSEMBLY AND INSTALLATION ............8-10 LOWER UNIT GEARS-SHIMMING AND ADJUSTMENT ......8-19...
8-2 LOWER UNIT REMOVAL AND DISASSEMBLY Disconnect the spark plug cap from the spark plug before removing the lower unit. 1. Remove the four engine mounting bolts. Detach the power unit with the lower cover. 2. Remove the spring 1. 3.
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LOWER UNIT 8-3 7. Remove the gear oil drain plug 8 before the gear oil level plug 7 and drain the gear oil. 8. Remove the cotter pin 9 then detach the propeller 0. 9. Remove the shear pin A. 10.
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8-4 LOWER UNIT 14. Remove the two bolts H securing the propeller shaft bearing housing. 15. Remove the propeller shaft bearing housing I. 16. Remove the E-ring J. 17. Pull out the driveshaft K. 18. Take out the following parts. •...
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LOWER UNIT 8-5 19. Take out the following parts. • Forward gear N • Forward gear backup shim O DISASSEMBLY OF PROPELLER SHAFT COMPONENTS 1. Separate the following parts. • Bearing housing 1. • Washer 2. • Propeller shaft assy 3. 2.
8-6 LOWER UNIT INSPECTION NOTE: If excessive wear, crack, defective or other damage is found on any component, replace. PROPELLER • Inspect the propeller. If bend, chip or other damage is found on the blades, replace or repair the propeller. •...
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LOWER UNIT 8-7 PROPELLER SHAFT COMPONENTS • Inspect the push rod. If excessive wear or other damage is found, replace. • Inspect the clutch dog shifter. If excessive wear, crack, chip or other damage is found, replace. • Inspect the return spring. If excessive wear or other damage is found, replace.
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(one at a time) 4. Apply the Water Resistant Grease to the seal lips. 99000-25161: SUZUKI WATER RESISTANT GREASE WATER PUMP AND RELATED ITEMS • Inspect the impeller. If cut, tear or excessive wear is found, replace the impeller.
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4. Apply the Water Resistant Grease to the seal lips. 09921-20210: Bearing remover 09930-30104: Sliding hammer 99000-25161: SUZUKI WATER RESISTANT GREASE DRIVESHAFT Inspect the driveshaft. If wear, twist or other damage is found on the splines, replace the driveshaft.
8-10 LOWER UNIT REASSEMBLY AND INSTALLATION Reassembly and installation is reverse of removal and disassembly with the special attention to the following steps. 5 N . m (0.5 kg-m, 3.5 lb-ft) 1. Clutch lever knob 2. Clutch lever pin 3. Clutch lever 4.
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LOWER UNIT 8-11 8 N . m 0.8 kg-m 6.0 lb-ft 30. Driveshaft bush 37. Push rod 44. Propeller shaft housing 31. Driveshaft 38. Return spring 45. Bolt 32. E-ring 39. Propeller shaft circlip 46. Propeller shaft housing oil seal 33.
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Apply the gear oil to the following parts. • Forward gear backup shim 2 • Forward gear 1 99000-22540: SUZUKI OUTBOARD MOTOR GEAR OIL NOTE: The forward gear has the bushing and the dents at the side of the dog bosses.
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• Apply the Water Resistant Grease to the oil seal lips. 99000-25161: SUZUKI WATER RESISTANT GREASE • Apply the gear oil to the bushing in the housing. 99000-22540: SUZUKI OUTBOARD MOTOR GEAR OIL • Install the driveshaft 1. • Install the E-ring 2.
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• Apply the Water Resistant Grease to the O-ring 4 and the oil seals of the bearing housing. 99000-25161: SUZUKI WATER RESISTANT GREASE • Install the propeller shaft/housing assembly to the gearcase and tighten the two bolts to the specified torque.
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• Install the under panel 2. • Install the impeller pin 3. • Install the impeller 4. • Apply SUZUKI BOND “1207B” onto the outer-surface of water pump sleeve 5. 99000-31140: SUZUKI BOND “1207B” • Install the water pump sleeve into the water pump case 6 by confirming the boss on the sleeve should be meeting with the groove on the pump case.
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8-16 LOWER UNIT WATER PUMP AND RELATED ITEMS • Install the water pump case 9 while rotating the driveshaft clockwise in order to flex the impeller vanes in the correct direction. • Tighten the water pump case bolts 0 to the specified torque. ...
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If the pressure does not fall, sealing performance is correct. PROPELLER • Apply the Water Resistant Grease to the propeller shaft. 99000-25161: SUZUKI WATER RESISTANT GREASE • Install the shear pin 1 and propeller 2. • Push the cotter pin 3 through the propeller shaft, then bend the pin securely.
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• Install the E-ring 5. • Install the clutch notch spring 6. • Shift the clutch lever from neutral and forward to check. GEAR OIL Fill the gearcase with the specified gear oil. (See page 2-5.) 99000-22540: SUZUKI OUTBOARD MOTOR GEAR OIL...
LOWER UNIT 8-19 LOWER UNIT GEARS-SHIMMING AND ADJUSTMENT If the lower unit has been rebuilt or has had components replaced, shimming for correct gear contact and backlash will have to be adjusted in order to ensure smooth, reliable opera- tion of gears. Shim/Washer and Mounting position Available Design...
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8-20 LOWER UNIT Adjusting gear backlash (Pinion and Forward gear) To check the backlash, hold the pinion gear by hand, then gently rock forward gear back and forth by hand. Gear backlash: 0.10 – 0.20 mm (0.004 – 0.008 in) •...
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LOWER UNIT 8-21 Optimum tooth contact Optimum tooth contact The optimum tooth contact is shown in the figure. Approx. 1/3 of tooth width A shim adjustment may be necessary in order to obtain the opti- Approx. 1 mm mum tooth contact pattern. HEEL ...
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8-22 LOWER UNIT CHECKING PROPELLER SHAFT THRUST PLAY After adjusting all gear positions, measure the propeller shaft thrust play. Propeller shaft thrust play: 0.20 – 0.40 mm (0.008 – 0.016 in) Measurement step 1. Assemble the gear adjusting gauge to the propeller shaft as shown in the figure.
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9-2 WIRE AND HOSE ROUTING HOSE ROUTING • Do not over-bend (kink) or twist hoses when installing. • When installing hose clips, position tab to avoid contact with other parts. • Check that hoses do not contact rods and levers during either engine operation or standstill. •...
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WIRE AND HOSE ROUTING 9-3 WIRE ROUTING...
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9-4 WIRE AND HOSE ROUTING WIRING DIAGRAM IGNITER UNIT SPARK PLUG FLYWHEEL MAGNETO Wire collor B: Black EMERGENCY STOP AND ENGINE STOP SWITCH Emergency stop switch: Lock plate IN Lock plate OUT STOP Engine stop switch: Button pushed STOP...
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Prepared by Service Department May, 2006 Manual No.99500-97J00-01E Printed in Japan...
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