Page 115 of 180
8-17
8
EBU38130Checking 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, C, and E. (See page 8-9.)
2. Remove the spark plug cap. 3. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s
tool kit.
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. Spark plug cap
1
UB5K60E0.book Page 17 Monday, May 28, 2018 11:35 AM
Page 116 of 180
8-18
8To 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-91. Spark plug gapSpark plug gap:0.8–0.9 mm (0.031–0.035 in)
UB5K60E0.book Page 18 Monday, May 28, 2018 11:35 AM
Page 117 of 180

8-19
8
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
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 speci-
fied torque as soon as possible. 3. Install the spark plug cap.
4. Install the panels.
EBU2746CEngine 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. Park 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.
Tightening torque:
Spark plug:13 N·m (1.3 kgf·m, 9.6 lb·ft)
UB5K60E0.book Page 19 Monday, May 28, 2018 11:35 AM
Page 118 of 180
8-20
84. Remove the engine oil 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.
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]
1. Access cover
1. Engine oil dipstick
1
1. Maximum level mark
2. Minimum level mark
UB5K60E0.book Page 20 Monday, May 28, 2018 11:35 AM
Page 119 of 180
8-21
8
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. Park the ATV on a level surface.
2. Start the engine, warm it up for several min- utes, 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.
TIPSkip steps 6–10 if the oil filter cartridge is not be-
ing replaced. 6. Remove panel F. (See page 8-9.)
7. Remove the oil filter cartridge with an oil filterwrench.1. Engine oil drain bolt
2. Gasket
12
UB5K60E0.book Page 21 Monday, May 28, 2018 11:35 AM
Page 120 of 180
8-22
8
TIPAn oil filter wrench is available at a nearby Yamaha
dealer. 8. Apply a thin coat of engine oil to the O-ring ofthe new oil filter cartridge.
TIPMake sure that the O-ring is properly seated. 9. 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
UB5K60E0.book Page 22 Monday, May 28, 2018 11:35 AM
Page 121 of 180

8-23
8
10. Install panel F.
11. Install the engine oil drain bolt and its new gasket, and then tighten the bolt to the spec-
ified torque. 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.
1. Torque wrenchTightening torque:
Oil filter cartridge:17 N·m (1.7 kgf·m, 13 lb·ft)
Tightening torque: Engine oil drain bolt:33 N·m (3.3 kgf·m, 24 lb·ft)
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)
UB5K60E0.book Page 23 Monday, May 28, 2018 11:35 AM
Page 122 of 180

8-24
8
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.EBU27308Final 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. Park the ATV on a level surface. 2. Remove the final gear oil level check bolt and
its gasket, and then check the oil level in the
final gear case. The oil level should be at the
brim of the check hole.
3. If the oil is below the brim of the check hole, remove the final gear oil filler bolt and its gas-
ket, and then add sufficient oil of the recom-
mended type to raise it to the correct level.
1. Final gear oil
2. Gasket
3. Final gear oil level check bolt
4. Correct oil level
1
243
UB5K60E0.book Page 24 Monday, May 28, 2018 11:35 AM