2010 YAMAHA GRIZZLY 550 engine

8-5
8
8*Wheel hub bearingsCheck for looseness or damage, and replace if
necessary.√ √√√
9*V- b e l tCheck for wear, cracks or other damage, and re-
place if necessary.√ √√√
10*Chassis fastenersMake sure that all nuts, bolts, and screws are
properly tightened.√√√√√
11*Shock absorber as-
sembliesCheck operation and correct if necessary.
Check for oil leakage and replace if necessary.√√√
12*Stabilizer bushesCheck for cracks or other damage, and replace if
necessary.√√√
13*Rear knuckle pivotsLubricate with lithium-soap-based grease.√√√
14*Steering shaftLubricate with lithium-soap-based grease.√√√
15*Steering systemCheck operation and repair or replace if damaged.
Check toe-in and adjust if necessary.√√√√√
16*Engine mountCheck for cracks or other damage, and replace if
necessary.√√√
17*Axle bootsCheck for cracks or other damage, and replace if
necessary.√√√√√
18 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√
19Engine oil filter car-
tridgeReplace.√√√ NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320
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8
EBU23211Checking 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 cap1
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.
To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque. Specified spark plug:
NGK/LMAR6A-9
Spark plug gap:
0.8–0.9 mm (0.031–0.035 in)
1. Spark plug gapTightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
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8-22
8
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.4. Install the spark plug cap.EBU27463Engine 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 10 minutes until the oil settles
for an accurate reading.
3. Remove panel F. (See page 8-8.)
4. 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.1. Engine oil dipstick
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TIPThe engine oil should be between the minimum
and maximum level marks.6. 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]
7. Insert the dipstick completely into the oil filler
hole.
8. Install the panel.To change the engine oil (with or without oil fil-
ter cartridge replacement)
1. Place the ATV on a level surface.
2. Remove panel F. (See page 8-8.)
3. Place an oil pan under the engine to collect
the used oil.
4. Remove the dipstick, and then remove the en-
gine oil drain bolt to drain the oil from the
crankcase.
TIPSkip steps 5–9 if the oil filter cartridge is not being
replaced.5. Remove panel G. (See page 8-8.)
1. Maximum level mark
2. Minimum level mark
1. Engine oil drain bolt
U28P61E0.book Page 23 Wednesday, March 18, 2009 9:25 AM

8-24
86. Remove the oil filter cartridge with an oil filter
wrench.
TIPAn oil filter wrench is available at a nearby Yamaha
dealer.7. 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.8. 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
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8-25
8
9. Install panel G.
10. Install the engine oil drain bolt, and then tight-
en it to the specified torque.11. 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.NOTICEECB00300
In 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 Nm (1.7 m·kgf, 12 ft·lbf)
Tightening torque:
Engine oil drain bolt:
30 Nm (3.0 m·kgf, 22 ft·lbf)
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 car tridge replacement:
2.10 L (2.22 US qt, 1.85 Imp.qt)
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8

Make sure that no foreign material enters the
crankcase.12. 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.
13. Turn the engine off, wait at least ten minutes,
and then check the oil level and correct it if
necessary.
14. Install panel F.EBU27304Final 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 level check bolt, 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 then
add sufficient oil of the recommended type to
raise it to the correct level.1. Final gear oil
2. Final gear oil level check bolt
3. Correct oil level
U28P61E0.book Page 26 Wednesday, March 18, 2009 9:25 AM