2008 YAMAHA WOLVERINE 450 engine

8-45
83. Install the panel.
EBU24900Checking and lubricating the cables The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02130Inspect cables frequently and replace if dam-
aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could re-
strict the operation of controls and lead to anaccident or injury.EBU28710Checking and lubricating the front and
rear brake levers The operation of the front and rear brake levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
1. Brake light switch
2. Brake light switch adjusting nutRecommended lubricant:
Engine oil
Recommended lubricants:
Front brake lever:
Silicone grease
Rear brake lever:
Lithium-soap-based grease (all-purpose
grease)
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8-56
8
EBU25781Troubleshooting charts Starting 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 compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
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.
Have a Yamaha dealer
check the ATV.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
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8-57
8Engine overheating
WARNING
EWB02290Wait 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.NOTE:If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the rec-ommended 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 NOTE.)
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.
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9-1
9
EBU25860
CLEANING AND STORAGE
EBU25880Cleaning Frequent, thorough cleaning of your ATV will not
only enhance its appearance but will improve its
general performance and extend the useful life of
many components.
1. Before cleaning the ATV:
a. Block off the end of the exhaust pipe to
prevent water entry. A plastic bag and
strong rubber band may be used.
b. Make sure the spark plug and all filler caps
are properly installed.
2. If the engine case is excessively greasy, apply
degreaser with a paint brush. Do not apply de-
greaser to the wheel axles.
3. Rinse the dirt and degreaser off with a garden
hose. Use only enough pressure to do the job.CAUTION:ECB00710Excessive water pressure may cause water
seepage and deterioration of wheel bearings,
brakes, transmission seals and electrical de-
vices. Many expensive repair bills have result-ed from improper high-pressure detergent
applications such as those available in coin-
operated car washers.
4. Once most of the dirt has been hosed off,
wash all surfaces with warm water and mild,
detergent-type soap. An old toothbrush or bot-
tle brush is handy for hard-to-reach places.
5. Rinse the ATV off immediately with clean wa-
ter and dry all surfaces with a chamois, clean
towel or soft absorbing cloth.
6. Clean the seat with a vinyl upholstery cleaner
to keep the cover pliable and glossy.
7. Automotive type wax may be applied to all
painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
abrasives which may mar the paint or protec-
tive finish. When finished cleaning, start the
engine and let it idle for several minutes.
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9-2
9
WARNING
EWB02310Wet brakes may have reduced stopping ability,
increasing the chance of an accident. Test the
brakes after washing. Apply the brakes several
times at slow speeds to let friction dry out thelinings.EBU25932Storage Short-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover.CAUTION:ECB00720
Storing the ATV in a poorly ventilated 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 ammo-
nia) and areas where strong chemicals arestored.Long-term
Before storing your ATV for several months:
1. Follow all the instructions in the “Cleaning”
section of this chapter.
2. Turn the fuel cock lever to “OFF”.
3. Drain the carburetor float chamber by loosen-
ing the drain bolt; this will prevent fuel deposits
from building up. Pour the drained fuel into the
fuel tank.
4. Fill up the fuel tank and add fuel stabilizer (if
available) to prevent the fuel from deteriorat-
ing.
5. 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. Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1 oz
of stabilizer to each gallon of fuel)
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9-3
9 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.
6. Lubricate all control cables and the pivoting
points of all levers and pedals.
7. 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. Alternative-
ly, turn the wheels a little every month in order
to prevent the tires from becoming degraded
in one spot.
8. Cover the muffler outlet with a plastic bag to
prevent moisture from entering it.
9. Remove the battery and fully charge it. Store
it in a cool, dry place and charge it once a
month. Do not store the battery in an exces-
sively cold or warm place [less than 0 °C (30°F) or more than 30 °C (90 °F)]. For more in-
formation on storing the battery, see page
8-47.
NOTE:Make any necessary repairs before storing theATV.
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10-1
10
EBU25960
SPECIFICATIONS
Dimensions:Overall length:
1978 mm (77.9 in)
Overall width:
1063 mm (41.9 in)
Overall height:
1095 mm (43.1 in)
Seat height:
840 mm (33.1 in)
Wheelbase:
1233 mm (48.5 in)
Ground clearance:
220 mm (8.7 in)
Minimum turning radius:
3000 mm (118 in)Weight:With oil and fuel:
250.0 kg (551 lb)Engine:Engine type:
Liquid cooled 4-stroke, SOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
421.0 cm³
Bore × stroke:
84.5 × 75.0 mm (3.33 × 2.95 in)Compression ratio:
10.00 :1
Starting system:
Electric starter
Lubrication system:
Wet sump
Engine oil:Type:
SAE5W30 or SAE10W30 or SAE10W40 or SAE15W40
or SAE20W40 or SAE20W50
Recommended engine oil grade:
API service SG type or higher, JASO standard MA-20˚ -10˚ 0˚
10˚20˚ 30˚40˚50˚C
10W/30
15W/4020W/4020W/50
10W/40
5W/30
U3C262E0.book Page 1 Tuesday, June 26, 2007 3:36 PM

10-2
10
Engine oil quantity:
Without oil filter cartridge replacement:
2.30 L (2.43 US qt) (2.02 Imp.qt)
With oil filter cartridge replacement:
2.40 L (2.54 US qt) (2.11 Imp.qt)Final gear oil:Type:
SAE80 API GL-4 Hypoid gear oil
Quantity:
0.23 L (0.24 US qt) (0.20 Imp.qt)Differential gear oil:Type:
SAE80 API GL-4 Hypoid gear oil
Quantity:
0.35 L (0.37 US qt) (0.31 Imp.qt)Cooling system:Coolant reservoir capacity (up to the maximum level mark):
0.25 L (0.26 US qt) (0.22 Imp.qt)
Radiator capacity (including all routes):
1.32 L (1.40 US qt) (1.16 Imp.qt)Air filter:Air filter element:
Wet elementFuel:Recommended fuel:
Regular unleaded gasoline only
Fuel tank capacity:
14.5 L (3.83 US gal) (3.19 Imp.gal)
Fuel reserve amount:
4.5 L (1.19 US gal) (0.99 Imp.gal)
Carburetor:Manufacturer:
MIKUNI
Type x quantity:
BSR33 x 1Spark plug (s):Manufacturer/model:
NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:
Wet, centrifugal automaticTransmission:Primary reduction system:
V-belt
Secondary reduction system:
Shaft drive
Secondary reduction ratio:
39/24 × 24/18 × 33/9 (7.944)
Transmission type:
V-belt automatic
Operation:
Left hand operation
Forward gear:
38/23 (1.652)
Reverse gear:
29/17 (1.706)Chassis:Frame type:
Steel tube frame
U3C262E0.book Page 2 Tuesday, June 26, 2007 3:36 PM