2015 YAMAHA GRIZZLY 450 maintenance

8-14
8To install the panel
Place the panel in its original position.
EBU23224Checking 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 plug
1. Remove panel A. (See page 8-10.)
2. Remove the spark plug cap.
1. Panel E
1
1. Spark plug cap
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8-16
8To 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 panel.EBU30241Engine 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. Remove panel E. (See page 8-10.)
3. Check the engine oil level on a cold engine.
1. Spark plug gapSpark plug gap: 0.6–0.7 mm (0.024–0.028 in)
Tightening torque:Spark plug:18 Nm (1.8 m·kgf, 13 ft·lbf)
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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 panel E.EBU30271Final 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 level 1. Place the ATV on a level surface. 2. Remove the final gear oil filler bolt and its gas-
ket, and then check the oil level in the final
gear case. The oil level should be at the brim
of the filler hole.
3. If the oil is below the brim of the filler hole, add sufficient oil of the recommended type to
raise it to the correct level.
4. Check the oil filler bolt gasket for damage, and replace it if necessary.
5. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
1. Final gear oil filler bolt
2. Gasket
3. Final gear oil
4. Correct oil level1
2
3
4
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8
EBU23427Differential gear oilThe differential gear case must be checked for oil
leakage before each ride. If any leakage is found,
have a Yamaha dealer check and repair the ATV.
In addition, the differential gear oil level must be
checked and the oil changed as follows at the in-
tervals specified in the periodic maintenance and
lubrication chart.
To check the differential gear oil level1. Place the ATV on a level surface.
2. Remove the differential gear oil filler bolt and its gasket, and then check the oil level in the
differential gear case. The oil level should be
at the brim of the filler hole. 3. If the oil is below the brim of the filler hole, add
sufficient oil of the recommended type to
raise it to the correct level.
4. Check the gasket for damage, and replace it if necessary.
5. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
1. Differential gear oil filler bolt
2. Gasket
3. Differential gear oil
4. Correct oil levelTightening torque:Differential gear oil filler bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)
1
2
3
4
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8-26
88. 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.EBU27127To check the coolant level1. Place 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. 3. If the coolant is at or below the minimum levelmark, remove panel C to access the coolant
reservoir. (See page 8-10.)
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 panel. NOTICE: If coolant is not avail-
able, use distilled water or soft tap water
instead. Do not use hard water or salt wa-
Tightening torque:
Differential gear oil filler bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)1. Maximum level mark
2. Minimum level mark
1
2
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8-30
816. Start the engine, and then check for coolant
leakage.
TIPIf any leakage is found, have a Yamaha dealer
check the cooling system. 17. Install the panels and the front carrier.EBU23647Cleaning 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.
1. Place the ATV on a level surface.
2. Remove the seat. (See page 4-19.)
3. Remove the air filter case cover by unhookingthe air filter case cover holders.1. Air filter case check hose
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8
EBU23932V-belt case drain plugAfter riding in water deep enough to allow it to en-
ter the V-belt case, remove the V-belt case drain
plug to drain the water from the case.TIPIf water drains from the V-belt case after removing
the plug, have a Yamaha dealer check the ATV as
the water may affect other engine parts.
EBU23941Adjusting the carburetorThe carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the pe-
riodic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. There-
fore, most carburetor adjustments should be left
to a Yamaha dealer, who has the necessary pro-
fessional knowledge and experience. The adjust-
ment described in the following section, however,
may be performed by the owner as part of routine
maintenance.NOTICEECB00481The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
settings without sufficient technical knowl-
edge may result in poor performance of or
damage to the engine. EBU24011Adjusting 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.
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8
EBU24048Adjusting the throttle lever free playThe throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 3.0–5.0
mm (0.12–0.20 in) as shown. Periodically check
the throttle lever free play and, if necessary, adjust
it as follows.TIPThe engine idling speed must be checked, and
adjusted if necessary, before adjusting the throttle
lever free play. 1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turnthe throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b). 4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24061Valve clearanceThe valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
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