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8
EBU23080Removing and installing the panel The panel shown needs to be removed to perform
some of the maintenance jobs described in this
chapter. Refer to this section each time the panel
needs to be removed and installed.EBU23112Panel A
To remove the panelRemove the bolt, and then take the panel off.To install the panel
Place the panel in the original position and install
the bolt. NOTICE: When installing the panel, be
sure not to pinch the cables or wires.
[ECB00381]
EBU23212
Checking 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-
1. Panel A
1. Panel A
2. Bolt
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8dance 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).
TIPIf 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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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
EBU23317Engine 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.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 engine oil 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 minimum
and maximum level marks.1. Engine oil filler cap
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8-13
8 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.
NOTICE: Be sure the engine oil is at the
correct level, otherwise engine damage
may result.
[ECB00851]
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
To change the engine oil (with or without oil fil-
ter cartridge replacement)
1. Place the ATV on a level surface.2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Place an oil pan under the engine to collect
the used oil.
4. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase.
TIPSkip steps 5–7 if the oil filter cartridge is not being
replaced.5. Remove the oil filter cartridge with an oil filter
wrench.
1. Engine oil dipstick
2. Maximum level mark
3. Minimum level mark
1. Engine oil drain bolt
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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
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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