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8
EBU34190Checking 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 panels A and C. (See page 8-9.)
2. Remove the storage compartment by remov- ing the bolt. 3. Remove the spark plug cap.
Tightening torques:
Panel bolt:4.0 N·m (0.40 kgf·m, 3.0 lb·ft)
Footboard nut: 4.0 N·m (0.40 kgf·m, 3.0 lb·ft)
1. Storage compartment
2. Bolt
1. Spark plug cap
2 1
1
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8
4. 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 vehi-
cle 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 vehicle. 2. Check the spark plug for electrode erosionand 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.
1. Spark plug wrench
1
Specified spark plug:NGK/CPR7EA-9
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8
EBU2746AEngine 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, warm up the engine, and then wait at least
10 minutes until the oil settles 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.
1. Access cover
1. Engine oil dipstick
1
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8-21
85. Insert the dipstick completely into the oil filler
hole, and then remove it again to check the oil
level.
TIPThe engine oil should be between the minimum
and maximum level marks. 6. If the engine oil is at or below the minimumlevel 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.
[ECB00852]
7. Insert the dipstick completely into the oil filler hole.
8. Install the access cover by turning it clock- wise.
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 minu- tes, and then turn it off.
3. Remove the access cover by turning it coun- terclockwise.
4. Place an oil pan under the engine to collect the used oil.
5. Remove the dipstick, and then remove the engine oil drain bolt and its gasket to drain the
oil from the crankcase.
1. Maximum level mark
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8-24
8
12. 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.
13. 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.
14. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.
15. 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 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.EBU34201To check the coolant level1. Park 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 N·m (2.3 kgf·m, 17 lb·ft)
1. Maximum level mark
2. Minimum level mark
12
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8
3. If the coolant is at or below the minimum level
mark, remove panels A and C to access the
coolant reservoir. (See page 8-9.)
4. Remove the coolant reservoir cap, add cool- ant or distilled water to the maximum level
mark, install the reservoir cap, and then install
the panels. NOTICE: If coolant is not avail-
able, use distilled water or soft tap water
instead. Do not use hard water or salt wa-
ter since they are harmful to the engine. If
water has been used instead of coolant,
replace it with coolant as soon as possible,
otherwise the cooling system will not be
protected 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]
TIP The radiator fan is automatically switched on or
off according to the coolant temperature in the
radiator.
If the engine overheats, see page 8-67 for fur-
ther instructions. 1. Coolant reservoir capCoolant reservoir capacity (up to the maxi-
mum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
1
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818. When coolant begins to flow out of the bolt
hole, tighten the cylinder head air bleed bolt
to the specified torque.
19. Start the engine and let it idle for ten minutes.
20. Rev the engine five times.
21. Pour additional coolant into the radiator until it is full. 22. Stop the engine and allow it to cool. If the
coolant level has dropped after the engine
has cooled, add sufficient coolant until it
reaches the top of the radiator, and then in-
stall the radiator cap.
23. Start the engine, and then check for coolant leakage.
TIPIf any leakage is found, have a Yamaha dealer
check the cooling system. 24. Install the footboard by installing the boltsand nuts, and then tighten them to the speci-
fied torques.
1. Cylinder head air bleed boltTightening torque:Cylinder head air bleed bolt:10 N·m (1.0 kgf·m, 7.4 lb·ft)
1
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