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8-9
8
EBU23213Checking 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).1. Spark plug cap
1. Spark plug wrench
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8
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.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. Specified spark plug:
NGK/DR7EA
1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
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8-11
8
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 specified
torque as soon as possible.3. Install the spark plug cap.EBU2329GEngine oil and oil filter element The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element cleaned at the intervals speci-
fied 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.
Tightening torque:
Spark plug:
18 Nm (1.8 m·kgf, 13 ft·lbf)
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8-12
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 element cleaning)
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. NOTICE: When remov-
ing the engine oil drain bolt, the compres-
sion spring, oil strainer and O-ring will fall
out. Take care not to lose these parts.
[ECB00311]
1. Engine oil filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Minimum level markU1P066E0.book Page 12 Thursday, August 5, 2010 4:15 PM
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8
TIPSkip steps 5–12, 18, and 19 if the oil filter element
is not being cleaned.5. Remove the footboard by removing the bolts.6. Fully loosen the brake pedal free play adjust-
ing nut, and push the brake pedal downward.1. Engine oil drain bolt
2. O-ring
3. Compression spring
4. Oil strainer
1. Footboard
2. Bolt
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8-15
89. Clean the oil strainer and oil filter element with
solvent.10. Install the oil filter element and a new O-ring.
TIPMake sure that the O-ring is properly seated.11. Apply a thin coat of clean engine oil to the O-
ring.
12. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.
1. Adjusting nut
2. Oil filter element cover
3. Bolt
12
3
3
1. Oil filter element
2. O-ringTightening torque:
Oil filter element cover bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
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8 13. Apply a thin coat of clean engine oil to a new
O-ring.
14. Install the oil strainer, the compression spring,
the new O-ring and the engine oil drain bolt,
and then tighten the engine oil drain bolt to the
specified torque. NOTICE: Before installing
the engine oil drain bolt, be sure to install
the O-ring, compression spring and oil
strainer.
[ECB00321]
15. 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
1. Engine oil drain bolt
2. O-ring
3. Compression spring
4. Oil strainer
Tightening torque:
Engine oil drain bolt:
43 Nm (4.3 m·kgf, 31 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element removal:
1.50 L (1.59 US qt, 1.32 Imp.qt)
With oil filter element removal:
1.60 L (1.69 US qt, 1.41 Imp.qt)
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8a 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.16. 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.
17. Turn the engine off, wait at least ten minutes,
and then check the oil level and correct it if
necessary.
18. Install the footboard by installing the bolts, and
then tighten them to the specified torques.
19. Adjust the brake pedal free play. (See page
8-31.)
1. Footboard bolt A
2. Footboard bolt BTightening torques:
Footboard bolt A:
4.0 Nm (0.40 m·kgf, 2.9 ft·lbf)
Footboard bolt B:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
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