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8-11
8To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.
2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
TIPIf a torque wrench is not available when installing
a spark plug, a good estimate of the correct torque
is 1/4–1/2 turn past finger tight. However, the spark
plug should be tightened to the specified torque assoon as possible.
4. Install the spark plug cap.EBU23315Engine oil and oil filter cartridge The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter cartridge replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Place the ATV on a level surface. Specified spark plug:
NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1. Spark plug gap
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)
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8-12
8 2. Check the engine oil level on a cold engine.
TIPIf the engine was started before checking the oil
level, be sure to warm up the engine sufficiently,
and then wait at least ten minutes until the oil set-tles for an accurate reading.
3. Remove the engine oil filler cap, and then
wipe the dipstick off with a clean rag.
4. Insert the dipstick into the filler hole (without
screwing it in), and then remove it again to
check the oil level.
TIPThe engine oil should be between the minimumand maximum level marks.
5. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type to raise it to the correct level.
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
1. Engine oil filler cap
1. Dipstick
2. Maximum level mark
3. Minimum level mark
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8
TIPBe sure to wipe off spilled oil on any parts after theengine and exhaust system have cooled down.NOTICEECB00300In order to prevent clutch slippage (since the
engine oil also lubricates the clutch), do not
mix any chemical additives. Do not use oils
with a diesel specification of “CD” or oils of
a higher quality than specified. In addition,
do not use oils labeled “ENERGY CONSERV-
ING II” or higher.Make sure that no foreign material enters thecrankcase.9. Start the engine, and then let it idle for several
minutes while checking it for oil leakage. If oil
is leaking, immediately turn the engine off and
check for the cause.
10. Turn the engine off, wait at least ten minutes,
and then check the oil level and correct it if
necessary.
EBU28572Final gear oil The final gear case must be checked for oil leak-
age before each ride. If any leakage is found, have
a Yamaha dealer check and repair the ATV. In ad- Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter cartridge replacement:
2.20 L (2.33 US qt, 1.94 Imp.qt)
With oil filter cartridge replacement:
2.30 L (2.43 US qt, 2.02 Imp.qt)1.“CD” specification
2.“ENERGY CONSERVING II”
1
2
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8-16
8 dition, the final gear oil level must be checked and
the oil changed as follows at the intervals specified
in the periodic maintenance and lubrication chart.
To check the final gear oil level
1. Place the ATV on a level surface.
TIPThe final gear oil level must be checked on a coldengine.
2. Remove the final gear oil filler bolt, and then
check the oil level in the final gear case.TIPThe oil level should be at the brim of the filler hole.
3. If the oil is below the brim of the filler hole, add
sufficient oil of the recommended type to raise
it to the correct level.
4. Install the oil filler bolt, and then tighten it to the
specified torque.
To change the final gear oil
1. Place the ATV on a level surface.
1. Final gear oil filler bolt
2. Correct oil level
3. Final gear oilTightening torque:
Final gear oil filler bolt:
24 Nm (2.4 m·kgf, 17 ft·lbf)
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8-18
8
TIPIf the recommended oil is not available, SAE80W-
90 API GL-5 Hypoid gear oil may be used instead.
However, when using this oil, noise from the final
gear case may occur when applying the rearbrake.
NOTICEECB00420Be sure no foreign material enters the finalgear case.
7. Install the oil filler bolt, and then tighten it to the
specified torque.
8. Check the final gear case for oil leakage. If oil
is leaking, check for the cause.
9. Install the engine guard and the final gear
case guard by installing the bolts, and then
tightening them to the specified torques.
1. Final gear oil filler bolt
2. Correct oil level
3. Final gear oilRecommended final gear oil:
See page 10-1.
Tightening torque:
Final gear oil filler bolt:
24 Nm (2.4 m·kgf, 17 ft·lbf)
Tightening torques:
Engine guard bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Final gear case guard bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
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8-19
8
EBU23422Differential gear oil The differential gear case must be checked for oil
leakage before each ride. If any leakage is found,
have a Yamaha dealer check and repair the ATV.
In addition, the differential gear oil level must be
checked and the oil changed as follows at the in-
tervals specified in the periodic maintenance and
lubrication chart.
To check the differential gear oil level
1. Place the ATV on a level surface.TIPThe differential gear oil level must be checked ona cold engine.
2. Remove the differential gear oil filler bolt, and
then check the oil level in the differential gear
case.
TIPThe oil level should be at the brim of the filler hole.
3. If the oil is below the brim of the filler hole, add
sufficient oil of the recommended type to raise
it to the correct level.
4. Install the oil filler bolt, and then tighten it to the
specified torque.1. Differential gear oil
2. Differential gear oil filler bolt
3. Correct oil levelTightening torque:
Differential gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
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8-23
86. Wash the sponge material gently but thor-
oughly in solvent.
WARNING
EWB01940Always use parts cleaning solvent to clean the
sponge material. Never use low-flash-point
solvents or gasoline to clean the sponge mate-
rial because the engine could catch fire or ex-plode.
7. Squeeze the excess solvent out of the sponge
material and let it dry.
NOTICEECB00440Do not twist the sponge material when squeez-ing it.
8. Check the sponge material and replace it if
damaged.
9. Apply a quality 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.
1. Air filter element frame
2. Sponge material
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8-24
8 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.
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 ar-
eas. Each time the air filter element maintenance
is performed, check the air inlet of the air filter case
for obstructions. Check the air filter case rubber
joint to the carburetor fittings and the rubber joint
manifold fittings for an air-tight seal. Tighten all fit-
tings securely to avoid the possibility of unfilteredair entering the engine.NOTICEECB00460Make sure that the air filter element is prop-
erly seated in the air filter case.Never operate the engine with the air filter el-
ement removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addition-
ally, operation without the air filter elementwill affect carburetor jetting with subsequent
poor performance and possible engine over-
heating.EBU27081Cleaning the spark arrester Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the bolts.
2. Remove the tailpipe by pulling it out of the
muffler.1. Bolt
2. Tailpipe
U4S262E0.book Page 24 Tuesday, June 10, 2008 11:40 AM