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EBU23214Checking the spark plugThe spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the
spark plug should be removed and checked in ac-
cordance with the periodic maintenance and lubri-
cation chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug1. Remove the spark plug cap. 2. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s
tool kit.
To check the spark plug 1. Check that the porcelain insulator around the center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).1. Spark plug cap1
1. Spark plug wrench
1
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TIPIf a torque wrench is not available when installing
the 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 speci-
fied torque as soon as possible. 3. Install the spark plug cap.EBU27468Engine oil and oil filter cartridgeThe 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
specified in the periodic maintenance and lubrica-
tion chart.
To check the engine oil level1. Place the ATV on a level surface.
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 10 minutes until the oil set-
tles for an accurate reading. 3. Remove the access cover by turning it coun- terclockwise.
4. Remove the engine oil dipstick, and then wipe it off with a clean rag.
Tightening torque:
Spark plug:13 Nm (1.3 m·kgf, 9.4 ft·lbf)1. Access cover
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11. Refill with the specified amount of the recom-
mended engine oil, and then insert the dip-
stick completely into the oil filler hole.
TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down. NOTICEECB00301In 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.
12. 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.
13. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.
14. Install the access cover by turning it clock- wise.EBU27307Final gear oilThe 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 speci-
fied in the periodic maintenance and lubrication
chart.
To check the final gear oil level1. Place the ATV on a level surface.
Recommended oil:
See page 10-1.
Oil quantity: Without oil filter cartridge replacement:2.00 L (2.11 US qt, 1.76 Imp.qt)
With oil filter cartridge replacement: 2.10 L (2.22 US qt, 1.85 Imp.qt)
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86. Check the oil level check bolt gasket and the
oil filler bolt gasket for damage, and replace
them if necessary.
7. Install the oil level check bolt, the oil filler bolt and their gasket, and then tighten the bolts to
the specified torques.
8. Check the final gear case for oil leakage. If oil is leaking, check for the cause.
EBU23427Differential gear oilThe 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.
2. Remove the differential gear oil filler bolt and its gasket, and then check the oil level in the
differential 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. Check the gasket for damage, and replace it if necessary.
Tightening torques:
Final gear oil level check bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Final gear oil filler bolt: 23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Differential gear oil filler bolt
2. Gasket
3. Differential gear oil
4. Correct oil level
1
2
3
4
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86. Check the oil filler bolt gasket for damage,
and replace it if necessary.
7. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
8. Check the differential gear case for oil leak- age. If oil is leaking, check for the cause.
EBU23471CoolantThe coolant level should be checked before each
ride. In addition, the coolant must be changed at
the intervals specified in the periodic maintenance
and lubrication chart.EBU27129To check the coolant level1. Place the ATV on a level surface.
TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture. 2. Check the coolant level in the coolant reser- voir.TIPThe coolant should be between the minimum and
maximum level marks.
Recommended differential gear oil:See page 10-1.
Tightening torque: Differential gear oil filler bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Maximum level mark
2. Minimum level mark
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EBU27808Cleaning the air filter elementThe air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean or, if necessary, replace
the air filter element more frequently if you are rid-
ing in unusually wet or dusty areas.TIPThere are two check hoses at the bottom of the air
filter case, which are located behind panels D and
E. (See page 8-10 for an explanation on removing
the panels.) Check the hoses periodically and, if
dust or water collects in them, empty them and
clean the air filter element and air filter case.
1. Place the ATV on a level surface.
2. Remove panel C. (See page 8-10.)1. Air filter case check hose
1. Air filter case check hose
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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.
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.1. V-belt case drain plug
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83. 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 must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.
EBU24072Adjusting the drive select lever safety
system cableThe drive select lever safety system cable stretch-
es with use, which can result in improper function.
Therefore, the safety system cable should be
checked and adjusted by a Yamaha dealer at the
intervals specified in the periodic maintenance
and lubrication chart.EBU29602BrakesReplacement of brake components requires pro-
fessional knowledge. Brake service should be
performed by a Yamaha dealer.
WARNING
EWB02572Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.
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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