2010 YAMAHA YFZ450R check engine

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8
EBU27695Troubleshooting chartsStarting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
Operate the electric starter.4. Compression
There is compression.
There is no compression.
The engine does not start.
Have a Yamaha dealer check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug. Have a Yamaha dealer check the ATV.
The engine does not start.
Check the compression.
DryWet
Operate the electric starter.
Have a Yamaha dealer check the ATV.
The engine does not start.
Check the ignition.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
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Engine overheating
WARNING
EWB02291Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap. TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the
recommended coolant as soon as possible. Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer check
and repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
U1TD61E0.book Page 52 Tuesday, July 8, 2014 11:30 AM

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abrasives which may mar the paint or protec-
tive finish. When finished cleaning, start the
engine and let it idle for several minutes.
EBU27262StorageShort-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover.
NOTICE: Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.
[ECB00722]
Long-term
Before storing your ATV for several months: 1. Follow all the instructions in the “Cleaning” section of this chapter.
2. Fill up the fuel tank and add fuel stabilizer (if available) to prevent the fuel from deteriorat-
ing. 3. Perform the following steps to protect the cyl-
inder, piston rings, etc. from corrosion.a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place the spark plug on the
cylinder head so that the electrodes are
grounded. (This will limit sparking during
the next step.)
d. Turn the engine over several times with the starter. (This will coat the cylinder wall
with oil.)
e. Remove the spark plug cap from the spark plug, and then install the spark plug and
the spark plug cap.
4. Lubricate all control cables and the pivoting points of all levers and pedals.
5. Check and, if necessary, correct the tire air pressure, and then block up the ATV so that
all of its wheels are off the ground. Alterna-
Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1
oz of stabilizer to each gallon of fuel)U1TD61E0.book Page 2 Tuesday, July 8, 2014 11:30 AM

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INDEX
AAccessories and loading ................................................ 6-5
Air filter element, cleaning ............................................ 8-21BBattery .......................................................................... 8-42
Brake and clutch levers, checking and lubricating ...... 8-39
Brake fluid, changing ...................................................8-31
Brake fluid level, checking ........................................... 8-29
Brake lever ..................................................................... 4-6
Brake lever free play, checking the front ..................... 8-31
Brake light switches ..................................................... 8-33
Brake pads, checking the front and rear ..................... 8-28
Brake pedal .................................................................... 4-6
Brake pedal, checking and lubricating ........................ 8-39
Brake pedal height, checking ...................................... 8-32
Brakes .......................................................................... 8-28
Brakes, front and rear .................................................... 5-4CCables, checking and lubricating ................................. 8-38
Chassis fasteners ........................................................... 5-7
Cleaning ......................................................................... 9-1
Clutch lever .................................................................... 4-5
Clutch lever free play, adjusting ................................... 8-34
Coolant ................................................................. 5-4, 8-20
Coolant temperature warning light ................................. 4-2
Cowling and panels, removing and installing .............. 8-10DDrive chain ..................................................................... 5-5
Drive chain, lubricating ................................................ 8-37 Drive chain slack .......................................................... 8-35
EEngine break-in .............................................................. 6-4
Engine oil ....................................................................... 5-4
Engine oil and oil filter element .................................... 8-14
Engine, start ................................................................... 6-1
Engine stop switch ......................................................... 4-3
Engine trouble warning light .......................................... 4-3FFuel ........................................................................ 4-9, 5-4
Fuel level warning light ................................................... 4-3
Fuel tank cap ................................................................. 4-8
Fuse, replacing ............................................................. 8-45HHandlebar position, adjusting ...................................... 4-24
Handlebar switches ....................................................... 4-3
Headlight beam, adjusting ........................................... 8-48
Headlight bulb, replacing ............................................. 8-45IIdentification numbers ................................................. 11-1
Indicator light and warning lights ................................... 4-2
Instruments, lights and switches ................................... 5-8LLabel locations ............................................................... 1-1
Light switch .................................................................... 4-4MMain switch .................................................................... 4-1
Maintenance and lubrication chart ................................ 8-5
Maintenance chart, emission control system ................ 8-3
U1TD61E0.book Page 1 Tuesday, July 8, 2014 11:30 AM