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8-35
8
14. When coolant begins to flow out of the bolt
hole, tighten the water pump air bleed bolt to
the specified torque.
15. Remove panel E. (See page 8-10.)
16. Loosen the cylinder head air bleed bolt, with- out removing it, to allow all of the air to es-
cape from the air bleed bolt hole. 17. When coolant begins to flow out of the bolt
hole, tighten the cylinder head air bleed bolt
to the specified torque.
18. Start the engine and let it idle for ten minutes.
19. Rev the engine five times.
20. Pour additional coolant into the radiator until it is full.
1. Water pump air bleed boltTightening torque:Water pump air bleed bolt:8 Nm (0.8 m·kgf, 5.8 ft·lbf)
1
1. Cylinder head air bleed boltTightening torque: Cylinder head air bleed bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1
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8-36
821. Stop the engine and allow it to cool. If the
coolant level has dropped after the engine
has cooled, add sufficient coolant until it
reaches the top of the radiator, and then in-
stall the radiator cap.
22. Start the engine, and then check for coolant leakage.
TIPIf any leakage is found, have a Yamaha dealer
check the cooling system. 23. Install the footboard by installing the boltsand nuts, and then tighten them to the speci-
fied torques.
TIPTighten footboard bolts B in the order shown. 1. Footboard nut
2. Footboard bolt A
3. Footboard bolt B
3
1
2
1
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8-39
8
6. Wash the sponge material gently but thor-
oughly in solvent. WARNING! Always use
parts cleaning solvent to clean the sponge
material. Never use low-flash-point sol-
vents or gasoline to clean the sponge ma-
terial because the engine could catch fire
or explode.
[EWB01942]
7. Squeeze the excess solvent out of the sponge material and let it dry. NOTICE: Do
not twist the sponge material when
squeezing it.
[ECB00442]
8. Check the sponge material and replace it if damaged.
9. Apply Yamaha foam air filter oil or other qual- ity foam air filter oil to the sponge material.TIPThe sponge material should be wet but not drip-
ping. 10. Pull the sponge material over the air filter ele- ment frame, and then install the lock plate.
11. Insert the air filter element into the air filter case, and then install the air filter case cover
by hooking the holders onto the air filter case.
NOTICE: Make sure that the air filter ele-
ment is properly seated in the air filter
1. Air filter element frame
2. Sponge material
3. Air filter element lock plate
3
2
1
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8-40
8case. Never operate the engine with the air
filter element removed. Doing so would al-
low unfiltered air to enter the engine, caus-
ing rapid engine wear and possible engine
damage. Additionally, the fuel injection
system would be affected resulting in poor
engine performance and possible over-
heating.
[ECB00763]
12. Install the seat.TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated
more often if the ATV is operated in extremely
dusty areas. Each time the air filter element main-
tenance is performed, check the air inlet of the air
filter case for obstructions. Check the air filter
case rubber joint to the throttle body and the rub-
ber joint manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU28904Cleaning the spark arresterBe sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the tailpipe bolts. 2. Remove the tailpipe by pulling it out of the
muffler, and then remove the gasket.
3. Tap the tailpipe lightly, and then use a wire brush to remove any carbon deposits from
the spark arrester portion of the tailpipe and
inside of the tailpipe housing.
1. Tailpipe bolt
1
1
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8-41
8
4. Check the gasket for damage, and replace it
if necessary.
5. Make sure the gasket is properly positioned, then insert the tailpipe into the muffler and
align the bolt holes.
6. Install the bolts and tighten them to the spec- ified torque.
WARNING
EWB02341Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components. EBU23932V-belt case drain plugAfter riding in water deep enough to allow it to en-
ter the V-belt case, remove the V-belt case drain
plug to drain the water from the case.TIPIf water drains from the V-belt case after removing
the plug, have a Yamaha dealer check the ATV as
the water may affect other engine parts.
1. Gasket
2. Spark arrester
3. TailpipeTightening torque:Tailpipe bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
3
2
1
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8-42
8
EBU29703Adjusting the throttle lever free playThe throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 3.0–5.0
mm (0.12–0.20 in) as shown. Periodically check
the throttle lever free play and, if necessary, adjust
it as follows.1. Slide the rubber cover back.
2. Loosen the locknut. 3. To increase the throttle lever free play, turn
the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24061Valve clearanceThe valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
1. V-belt case drain plug
1
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
2WD
4WD
3
2
1
4
(b)
(a)
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8-67
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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8-68
8Engine 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.
UB1660E0.book Page 68 Thursday, February 26, 2015 4:01 PM