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8
EBU23081Removing and installing the panelThe 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.EBU23102Panel A
To remove the panelRemove the bolts, and then take the panel off.To install the panel
Place the panel in the original position and install
the bolts.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.
1. Panel A
1
1. Panel A
2. Bolt
2
2
1
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8
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
1. Spark plug wrench
1
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EBU26788Engine oil and oil filter elementThe engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level1. Place the ATV on a level surface.
2. Start the engine, warm it up until the engine oil has reached a normal temperature of 60
°C (140 °F), let it continue to idle for ten sec-
onds or more, and then turn the engine off.TIPTo achieve the proper engine oil temperature for
an accurate oil level reading, the engine must have
first completely cooled down, and then warmed
up again for several minutes to normal operating
temperature. 3. Remove the engine oil tank filler cap, andthen wipe the engine oil dipstick off with a
clean rag.
4. Insert the dipstick in 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. 5. If the engine oil is at or below the minimumlevel mark, add sufficient oil of the recom-
mended type through the engine oil tank filler
hole to raise it to the correct level. NOTICE:1. Engine oil tank
2. Engine oil tank filler cap
3. Engine oil dipstick
4. Maximum level mark
5. Minimum level mark
2
3
4
5 1
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14. Remove the engine oil tank filler cap, and
then gradually fill the oil tank with the remain-
ing oil quantity while regularly checking the oil
level on the dipstick.
15. Install and tighten the engine oil tank filler cap.
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.
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, and then check the oil level and correct it if necessary.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.EBU27945To check the coolant level1. Place the ATV on a level surface.
Recommended oil:
See page 10-1.
Oil quantity: Without oil filter element replacement:1.75 L (1.85 US qt, 1.54 Imp.qt)
With oil filter element replacement: 1.85 L (1.96 US qt, 1.63 Imp.qt)
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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.
3. If the coolant is at or below the minimum levelmark, remove the coolant reservoir cap, add
coolant or distilled water to the maximum lev-
el mark, and then install the reservoir cap.
NOTICE: If coolant is not available, use
distilled water or soft tap water instead.
Do not use hard water or salt water since
they are harmful to the engine. If water has
been used instead of coolant, replace it
with coolant as soon as possible, other-
wise the cooling system will not be pro-
tected against frost and corrosion. If water
has been added to the coolant, have a
Yamaha dealer check the antifreeze con-
tent of the coolant as soon as possible,
otherwise the effectiveness of the coolant
will be reduced.
[ECB01012]
1. Maximum level mark
2. Minimum level mark
12
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9. Connect the coolant reservoir hose.
10. Pour the recommended coolant into the res- ervoir to the maximum level mark, and then
install the reservoir cap. NOTICE: Mix anti-
freeze with distilled water only. However, if
distilled water is not available, soft water
may be used for refilling. Do not use hard
water or salt water since they are harmful
to the engine.
[ECB00992]
11. Pour the recommended coolant into the radi- ator until it is full.
12. Install the radiator cap, start the engine, let it idle for several minutes, and then turn it off. 13. Remove the radiator cap to check the coolant
level in the radiator. If it is low, add sufficient
coolant until it reaches the top of the radiator,
and then install the radiator cap.
14. Start the engine, and then check for coolant leakage.
TIPIf any leakage is found, have a Yamaha dealer
check the cooling system. 15. Install the panel.EBU26808Cleaning 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 is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case.
Antifreeze/water mixture ratio:1:1
Recommended antifreeze: High-quality ethylene glycol antifreeze con-
taining corrosion inhibitors for aluminum
engines
Coolant quantity: Radiator (including all routes):1.68 L (1.78 US qt, 1.48 Imp.qt)
Coolant reservoir (up to the maximum level
mark): 0.25 L (0.26 US qt, 0.22 Imp.qt)
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15. Insert the air filter element into the air filter
case, and then tighten the wing bolt.
NOTICE: Make sure that the air filter ele-
ment is properly seated in the air filter
case. Never operate the engine with the air
filter element removed. Doing so would al-
low unfiltered air to enter the engine, caus-
ing rapid engine wear and possible engine
damage. Additionally, the fuel injection
system would be affected resulting in poor
engine performance and possible over-
heating.
[ECB00763]
16. Install the air filter case cover by hooking the holders onto the air filter case. 17. Install the seat.
TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated
more often if the ATV is operated in extremely
dusty areas. Each time the air filter element main-
tenance is performed, check the air inlet of the air
filter case for obstructions. Check the air filter
case rubber joint to the throttle body and the rub-
ber joint manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU30861Cleaning the spark arresterSelect a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the tailpipe cover by removing the bolts.
1. Washer
1
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4. Install the gasket, tailpipe, and retainer and
align the bolt holes.
5. Install the bolts and tighten them to the spec- ified torque.
6. Install the tailpipe cover and align the bolt holes.
7. Install the bolts and tighten them to the spec- ified torque.
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. EBU26812Adjusting the engine idling speedThe engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance and lubrica-
tion chart.TIPA diagnostic tachometer is needed to make this
adjustment. 1. Start the engine and warm it up.
2. Attach the tachometer to the spark plug lead.
1. Tailpipe
2. Spark arresterTightening torque:Retainer bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1
2
Tightening torque: Tailpipe cover bolt:8 Nm (0.8 m·kgf, 5.8 ft·lbf)
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