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8-2
8The service information included in this manual
and the tools provided in the owner’s tool kit are in-
tended to assist you in the performance of preven-
tive maintenance and minor repairs. However,
additional tools such as a torque wrench may be
necessary to perform certain maintenance work
correctly.
TIPIf you do not have the tools or experience required
for a particular job, have a Yamaha dealer perform
it for you.1. Owner’s manual
2. Owner’s tool kit
3. Low-pressure tire gaugeU1AB60E0.book Page 2 Wednesday, April 29, 2009 10:19 AM
Page 91 of 142
8-11
8 2. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
3. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.To install the spark plug
1. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
2. 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 as
soon as possible.3. Install the spark plug cap. Specified spark plug:
NGK/DR8EA
1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)
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8-14
8
TIPAn oil filter wrench is available at a nearby Yamaha
dealer.6. Apply a thin coat of engine oil to the O-ring of
the new oil filter cartridge.TIPMake sure that the O-ring is properly seated.7. Install the new oil filter cartridge with an oil fil-
ter wrench, and then tighten it to the specified
torque with a torque wrench.
1. Oil filter cartridge
1. Oil filter wrench
1. O-ring
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8-15
8
8. Install the engine oil drain bolt, and then tight-
en it to the specified torque.
9. Refill with the specified amount of the recom-
mended engine oil, and then install and tight-
en the engine oil filler cap.
TIPBe sure to wipe off spilled oil on any parts after the
engine 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 the
crankcase.
1. Torque wrenchTightening torque:
Oil filter cartridge:
17 Nm (1.7 m·kgf, 12 ft·lbf)
Tightening torque:
Engine oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
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 car tridge replacement:
2.30 L (2.43 US qt, 2.02 Imp.qt)
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8-16
810. 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.
11. Turn the engine off, wait at least ten minutes,
and then check the oil level and correct it if
necessary.
EBU23384Final 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-
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 when the
engine is cold.2. Remove the final gear oil filler bolt, and then
check the oil level in the final gear case. The
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
2. Final gear oil filler bolt
3. Correct oil levelTightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
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8-17
8 2. Remove the final gear case guard by remov-
ing the bolts.
3. Place an oil pan under the final gear case to
collect the used oil.
4. Remove the final gear oil filler bolt and the fi-
nal gear oil drain bolt to drain the oil from the
final gear case.5. Install the drain bolt, and then tighten it to the
specified torque.
6. Refill with the recommended final gear oil to
the brim of the filler hole as shown. NOTICE:
Be sure no foreign material enters the final
gear case.
[ECB00421]
1. Final gear case guard
2. Bolt
1. Final gear oil drain boltTightening torque:
Final gear oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
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8-18
8
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 final gear case guard by installing
the bolts and tightening them to the specified
torque.
EBU23434Changing the differential 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 must be
changed as follows at the intervals specified in the
periodic maintenance and lubrication chart.
1. Place the ATV on a level surface.
2. Place an oil pan under the differential gear
case to collect the used oil.
3. Remove the differential gear oil filler bolt and
the differential gear oil drain bolt to drain the
oil from the differential gear case.
1. Final gear oil
2. Final gear oil filler bolt
3. Correct oil levelRecommended final gear oil:
See page 10-1.
Tightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
Tightening torque:
Final gear case guard bolt:
16 Nm (1.6 m·kgf, 11 ft·lbf)
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8
4. Install the drain bolt, and then tighten it to the
specified torque.5. Refill with the specified amount of the recom-
mended differential gear oil. NOTICE: Be
sure no foreign material enters the differ-
ential gear case.
[ECB00411]
TIPDo not exceed the specified differential gear oil
quantity when filling. Overfilling will cause the oil
to seep out of the breather hose during and after
riding.The differential gear case capacity is greater
than the recommended oil quantity, therefore
the oil level cannot be accurately checked from
the oil filler hole.6. Install the oil filler bolt, and then tighten it to the
specified torque.
1. Differential gear oil filler bolt
1. Differential gear oil drain bolt
Tightening torque:
Differential gear oil drain bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Recommended differential gear oil:
See page 10-1.
Oil quantity:
0.35 L (0.37 US qt, 0.31 Imp.qt)
U1AB60E0.book Page 19 Wednesday, April 29, 2009 10:19 AM