Model : MX825V-EFI FEATURE MAP Fuel injection system Debris screen Donaldson® cyclone-type air Fan case cover (good fuel efficiency & (reduces the amount of grass cleaner (good maintainability) performance, emission) clippings and other debris entering the flywheel/cooling fan area) 75 degree V-bank angle (compact engine)...
Model : MX825V-EFI Specification MX825V-EFI ECV 880 Vanguard 810 FX850V Model Name Yamaha Kohler B&S Kawasaki Dimensions* (in.) L x W x H 19.6 x 18.3 x 25.2 19.7 x 20.5 x 24 19.9 x 18.5 x 22.9 18.9 x 18.1 x 24.2 Weight –...
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Model : MX825V-EFI Part Content Crankshaft • Adopt 30 degree phase shift crank pins with internal oil passages Theme 1) 30 degree phase shift design 2) Internal oil passageways • Reduces vibration, and the number of parts required • Balancer weight not needed to reduce vibration...
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Model : MX825V-EFI Part Content Valve system • 2 inlet Valves. Theme 1) Multi valve (2 IN, 1 EX) , 2) Shim valve adjustment design. • Adopt shim valve adjustment design. Target 1) High performance, 2) Long maintenance interval. Valve springs for intake are...
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Model : MX825V-EFI Part Content Fan Case Cover • Fan case consists of 2 pieces - Fan case and Fan case cover Theme Fan Case Cover consists of 2 parts • There are 2 maintenance hatch under fan case cover...
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Model : MX825V-EFI Part Content Debris Screen • Debris screen is installed to reduce the amount of grass clippings from Theme Adopt Debris Screen entering the flywheel/cooling fan area Target To reduce grass clippings from clogging and easy maintenance Debris screen...
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Model : MX825V-EFI Part Content Lubrication • Forced lubrication system with trochoid pump Theme Forced lubrication system • Trochoid pump with oil strainer and pressure relief valve • Oil Cooler incorporated (air-cooled, radiator type) Target Superior engine lubrication, reliability and reduced wear...
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Model : MX825V-EFI SERVICE TIP Continuation of previous page (Oil supply) Oil spray goes into cylinder head through hole. Spray oil to cylinder head Supplied to Camshaft Supplied to Camshaft Camshaft Supplied to Crankshaft (refer to crankshaft page )
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Model : MX825V-EFI Part Content Oil filter • Oil filter is positioned at a slight angle for easier access during service Theme Oil filter position • The oil filter mount on the lower crankcase assy has integral oil catch tray to help catch dripped oil from the filter...
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Element Assy, Outer Element Assy, Inner Performance for customer Service Tip • Periodical maintenance Nothing ruins an engine faster than dirt, that's why Yamaha chose a commonly available 2-stage design to maximize engine protection. Replace outer element: 250hr Check Inner element :...
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Model : MX825V-EFI Part Content Fuel Injection system • Fuel Injection system to balance fuel efficiency with performance and Theme Fuel Injection System reduce harmful exhaust emissions Target Best possible fuel efficiency, performance, emission & reliability Fuel pump MAP / MAT...
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Model : MX825V-EFI SERVICE TIP Throttle Body, w/ Throttle Position Continuation of previous page (FI system) Sensor Injector #2 Injector #1 Use inch tool ENG Temp MAP/MAT “5/8” or 16mm For ENG temp sensor Ignition Coil #1 Ignition Coil #2...
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Model : MX825V-EFI Part Content Cover, Crankcase 1 • 2 large bearings are installed in Cover, Crankcase 1, which becomes the Theme Bearings (for camshaft and crankshaft) bottom side of engine. Target Reduce internal engine friction Ball Bearings (Bottom side of Crankshaft, Camshaft)
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Performance for customer Service Tip • Pistons are installed with the arrow on the piston Compact size engine. crown pointed to the intake side of the engine (this differs from the standard Yamaha practice, where the arrow points to the exhaust)
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Service Tip • Small, easy to use tool which is very durable. • FI Diagnostic Tool will be available from Yamaha Parts • Inexpensive enough for every mechanic to have their own, the target MSRP is $150.00 and Accessories Division •...
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Model : MX825V-EFI SERVICE TIP Continuation of previous page (FI diagnostic Tool) Main 5 modes of Diag tool “CURRENT” “HISTORY” “DIAG” DOWN DOWN DOWN DOWN DOWN “PROPERTY” “CLEAR” Display of Diag Tool (Selecting Mode) Display has 2 lines. Upper line shows which mode you choose now or what you’re doing.
Model : MX825V-EFI SERVICE TIP Continuation of previous page (FI diagnostic Tool) More information on the FI Diagnostic tool is provided in the Sensor outputs – FI Diagnostic Tool Display MX825 EFI Seminar literature Items What to detect Unit Intake air pressure Intake air temp Temp °F...
Model : MX825V-EFI SERVICE TIP Wiring Schematic – Equipment Information The equipment manufacturer supplies the following components, including wiring and connectors as needed: 1. Battery 2. Main Switch 3. MIL lamp 4. Oil Pressure Warning lamp 5. ‘Ground to Stop Engine’ circuit (e.g., seat switch or rollover...
Model : MX825V-EFI SERVICE TIP Oil Pressure Switch Operation Engine running with Oil pressure less than Condition normal oil pressure Engine not running 7.1 psi (49 kPA) The Oil Pressure Switch completes the ground circuit for the Oil Pressure Warning light:...
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Model : MX825V-EFI SERVICE TIP Shim Valve Adjustment Overview Valve clearance is measured by inserted a feeler gauge, in the specified thickness range*, between the rocker arm and the valve adjustment shim as shown in the illustration. • If the clearance is excessive, the valve adjustment shim is replaced with a thicker shim.
Model : MX825V-EFI SERVICE TIP Valve Adjustment Procedure 1. Place the first cylinder at TDC on the compression stroke (either cylinder, order is not critical). 2. Measure the clearance between the rocker arm and the valve adjustment shim, as shown in the illustration, using the Go – No Go system.
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Model : MX825V-EFI SERVICE TIP Fuel Pump System Operation • The positive and negative pressure pulses created in the crankcase during engine operation move a diaphragm assembly inside the vacuum pump (1) back and forth – detected through hose (2) •...
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OWNER’S MANUAL MX775 Read this manual carefully before operating this machine. MX800 MX825 LIT-19626-02-37 7UD-F8199-60-E0...
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Cover page 2 Read this manual carefully before operating this machine. This manual should stay with this machine if it is sold.
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Therefore, while this manual contains the most current product information available at the time of printing, there may be minor discrepancies between your machine and this manual. If there is any question concerning this manual, please consult a Yamaha dealer.
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Important manual information Particularly important information is distinguished in this manual by the following nota- tions. This is the safety alert symbol. It is used to alert you to potential personal injury hazards. Obey all safety messages that follow this symbol to avoid possible injury or death.
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Contents Safety information ....1 Consumer information ... 23 General safety information ....1 Machine identification ....... 23 Exhaust fumes are poisonous..... 1 Identification number records.... 23 Fuel is highly flammable and Exhaust emission control poisonous..........1 system and components ..24 Engine and muffler may be hot ...
Safety information General safety information • Do not allow children to operate the multi-purpose engine. • Do not place any obstacles on the multi-purpose engine. • Do not sit or stand on the multi-purpose engine. Exhaust fumes are poisonous • Using a multi-purpose engine indoors CAN KILL YOU IN MINUTES.
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Safety information • Take care not to spill any fuel on the engine or muf- fler when refueling. • Do not leave the multi-purpose engine inside the vehicle or in the trunk. • If you swallow any fuel, inhale fuel vapor, or allow any to get in your eye(s), see your doctor immediately.
Safety information Engine and muffler may be hot • Place the machine in a place where pedestrians or children are not likely to touch the machine. • Avoid placing any flammable materials near the exhaust outlet during operation. • In order to prevent overheating, ensure adequate air- flow by keeping the machine at least 1 m (3 ft) from objects or other equipment.
Safety information • When covering the multi-purpose engine, be sure to do so only after the engine and muffler have com- pletely cooled down. Electric shock prevention • Never operate the engine in rain or snow. • Never touch the machine with wet hands or electrical shock will occur.
Safety information Location of important labels Please read the following labels carefully before operating this machine. Maintain or replace safety and instruction labels, as necessary. CAN ICES-2/NMB-2 7CN-H2377-00...
Before operation Preparation Engine oil The multi-purpose engine has been shipped with- out engine oil. Do not start the engine until you have filled it with the sufficient engine oil. Place the multi-purpose engine on a level surface. Remove the oil filler cap. 1.
- If necessary, add recommended oil to specified level. (See page 7 for more details.) - Check multi-purpose engine for oil leakage. • The point where abnormality was recognized by - Check operation. - If necessary, consult a Yamaha dealer.
Operation Precautions for use WARNING Never operate the engine in a closed area or it may cause unconsciousness and death within a short time. Operate the engine in a well ventilated area. The multi-purpose engine has been shipped with- out engine oil. Do not start the engine until you have filled it with the sufficient engine oil.
The most important points of multi-purpose engine inspection, adjustment, and lubrication are explained on the following pages. WARNING If you are not familiar with maintenance work, have a Yamaha dealer do it for you. Maintenance schedule Maintenance chart WARNING Stop the engine before starting maintenance work.
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Periodic maintenance 1000 Daily 50 hrs 100 hrs 200 hrs 250 hrs 500 hrs The point where abnormality was recognized by use. *1 For models equipped with a Yamaha muffler. *2 Have a Yamaha dealer perform the service.
Periodic maintenance Spark plug inspection The spark plugs are important engine components, which should be checked periodically. Remove the spark plug caps and the spark plugs. 1. Spark plug cap Check for discoloration and remove the carbon. The porcelain insulator around the center elec- trode of spark plug should be a medium-to-light tan color.
Remove the oil filter cartridge with an oil filter wrench. 1. Oil filter wrench 2. Oil filter cartridge An oil filter wrench is available at a Yamaha dealer. Apply a thin coat of clean engine oil to the O-ring of the new oil filter cartridge. 1. O-ring...
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Engine oil quantity: 2.0 L (2.11 US qt, 1.76 Imp qt) Start the engine and let it idle for several minutes while checking for oil leaks. If oil is leaking, immediately turn the engine off and consult a Yamaha dealer.
Periodic maintenance Turn the engine off and wipe the engine oil dipstick clean, insert it back into the oil filler hole (without screwing it in), and then remove it again to check the oil level. 1. Minimum level mark 2. Maximum level mark 3.
Periodic maintenance The engine should never run without the air filter element; excessive piston and cylinder wear may result. Install the air filter case cover. Place the holding clips in the original position. Remove the dust cap on the air filter case cover for accumulated dirt or water.
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Periodic maintenance Use a flathead screw driver to pry out and remove the spark arrester from the muffler. 1. Spark arrester Remove the carbon deposits on the spark arrester using a wire brush. When cleaning, use the wire brush lightly to avoid damaging or scratching of the spark arrester.
Storage Long term storage of your machine will require some preventive procedures to guard against deterioration. Add fuel stabilizer Fill up the fuel tank and add fuel stabilizer to prevent the fuel tank from rusting and the fuel from deteriorat- ing.
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Storage Clean exterior of the multi-purpose engine and apply a rust inhibitor. Store the multi-purpose engine in a dry, well-venti- lated place, with the cover placed over it. The multi-purpose engine must remain in a vertical position when stored, carried or operated.
Troubleshooting Engine won’t start Check the engine oil system. Add engine oil, if the engine oil level is low. Consult a Yamaha dealer, if the engine oil level is correct. Check the spark plug. WARNING • To prevent FIRE HAZARDS be sure fuel is not present in the spark plug area.
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Specified fuse: 30 A 1, 10 A • If the fuse immediately blows again, consult a Yamaha dealer. • For the 30 A fuse, there is identification red tape on the wire harness. Install the fuse holder to the original position.
Record your model type, Primary I.D., and serial num- bers in the spaces provided, to assist you in ordering spare parts from a Yamaha dealer. Also record and keep these I.D. numbers in a separate place in case your machine is stolen.
ENGINES and the CALIFORNIA REGULATIONS FOR 1995 AND LATER SMALL OFFROAD ENGINES. The acronyms conform to the latest version of the SAE’s recommended practice docu- ment J1930, “Diagnostic Acronyms, Terms, and Definitions For Electrical/Electronic System”. It is recommended that these items be serviced by a Yamaha dealer.