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EBU23211Checking the spark plug The 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 accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug
1. 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).
NOTE:If the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-stead, have a Yamaha dealer check the ATV.
1. Spark plug cap
1. Spark plug wrench
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82. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
To 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. Specified spark plug:
NGK/CPR7EA-9
Spark plug gap:
0.8–0.9 mm (0.031–0.035 in)
1. Spark plug gapTightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
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NOTE:If 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.EBU27461Engine 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.
2. Check the engine oil level on a cold engine.NOTE:If 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 settlesfor an accurate reading.
3. Remove panel F. (See page 8-8.)4. Remove the dipstick, and then wipe it off with
a clean rag.
5. Insert the dipstick completely into the oil filler
hole, and then remove it again to check the oil
level.
1. Dipstick
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NOTE:The engine oil should be between the minimumand maximum level marks.
6. 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.
7. Insert the dipstick completely into the oil filler
hole.
8. Install the panel.
CAUTION:ECB00850Be sure the engine oil is at the correct level,otherwise engine damage may result.
To change the engine oil (with or without oil fil-
ter cartridge replacement)
1. Place the ATV on a level surface.
2. Remove panel F. (See page 8-8.)
3. Place an oil pan under the engine to collect
the used oil.
4. Remove the dipstick, and then remove the en-
gine oil drain bolt to drain the oil from the
crankcase.
1. Maximum level mark
2. Minimum level mark
1. Engine oil drain bolt
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8
NOTE:Skip steps 5–9 if the oil filter cartridge is not beingreplaced.
5. Remove panel G. (See page 8-8.)
6. Remove the oil filter cartridge with an oil filter
wrench.NOTE:An oil filter wrench is available at a nearby Yamahadealer.
7. Apply a thin coat of engine oil to the O-ring of
the new oil filter cartridge.
NOTE:Make sure that the O-ring is properly seated.
8. 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
2. Oil filter wrench
1. O-ring
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9. Install panel G.
10. Install the engine oil drain bolt, and then tight-
en it to the specified torque.11. Add the specified amount of the recommend-
ed engine oil, and then insert the dipstick com-
pletely into the oil filler hole.
NOTE:Be sure to wipe off spilled oil on any parts after theengine and exhaust system have cooled down.CAUTION:ECB00300In 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.
1. Torque wrenchTightening torque:
Oil filter cartridge:
17 Nm (1.7 m·kgf, 12 ft·lbf)
Tightening torque:
Engine oil drain bolt:
30 Nm (3.0 m·kgf, 22 ft·lbf)
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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Make sure that no foreign material enters thecrankcase.
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 panel F.EBU27302Final 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.NOTE:The final gear oil level must be checked on a coldengine.2. Remove the final gear oil level check bolt, and
then check the oil level in the final gear case.
NOTE:The oil level should be at the brim of the checkhole.
3. If the oil is below the brim of the check hole,
remove the final gear oil filler bolt, and then
add sufficient oil of the recommended type to
raise it to the correct level.1. Final gear oil
2. Final gear oil level check bolt
3. Correct oil level
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84. Install the oil level check bolt and oil filler bolt,
and then tighten them to the specified torques.
To change the final gear oil
1. Place the ATV on a level surface.
2. Place an oil pan under the final gear case to
collect the used oil.3. Remove the final gear oil filler bolt, final gear
oil level check bolt, and the final gear oil drain
bolt to drain the oil from the final gear case.
4. Install the drain bolt, and then tighten it to the
specified torque.
5. Add the recommended final gear oil to the
brim of the check hole as shown.
1. Final gear oil filler boltTightening 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. Final gear oil drain boltTightening torque:
Final gear oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
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