2010 YAMAHA GRIZZLY 450 engine

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EBU28783
PERIODIC MAINTENANCE AND ADJUSTMENT
EBU21671Periodic inspection, adjustment, and lubrication
will keep your vehicle in the safest and most effi-
cient condition possible. Safety is an obligation of
the vehicle owner/operator. The most important
points of vehicle inspection, adjustment, and lubri-
cation are explained on the following pages.
WARNING
EWB01841Failure to properly maintain the vehicle or per-
forming maintenance activities incorrectly may
increase your risk of injury or death during ser-
vice or while using the vehicle. If you are not fa-
miliar with vehicle service, have a Yamaha
dealer perform the service.
WARNING
EWB02561Turn off the engine when performing mainte-
nance unless otherwise specified.
A running engine has moving parts that can
catch on body parts or clothing and electri-
cal parts that can cause shocks or fires.

Running the engine while servicing can lead
to eye injury, burns, fire, or carbon monoxide
poisoning - possibly leading to death. See
page 2-1 for more information about carbon
monoxide.The intervals given in the periodic maintenance
and lubrication chart should be considered as a
general guide under normal riding conditions.
However, DEPENDING ON THE WEATHER,
TERRAIN, GEOGRAPHICAL LOCATION, AND
INDIVIDUAL USE, THE MAINTENANCE INTER-
VALS MAY NEED TO BE SHORTENED.EBU21731Owner’s manual and tool kit Be sure to put this owner’s manual in the plastic
bag and always carry it on the bottom of the seat
as shown. Put the owner’s tool kit and low-pres-
sure tire gauge under the seat.
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EBU21743Periodic maintenance chart for the emission control system TIP
For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should be followed.
Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,
data and technical skills.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
1*Fuel lineCheck fuel hoses for cracks or other damage, and
replace if necessary.√√√
2 Spark plugCheck condition and clean, regap, or replace if
necessary.√√√√√
3*ValvesCheck valve clearance and adjust if necessary.√ √√√
4*CarburetorCheck starter (choke) operation and correct if nec-
essary.
Check engine idling speed and adjust if neces-
sary.√√√√
5*Crankcase breather
systemCheck breather hose for cracks or other damage,
and replace if necessary.√√√
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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.√√√
20*Engine oil strainerClean.√√√
21 Differential gear oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√√
22 Final gear oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√√√
23 Cooling systemCheck coolant level and ATV for coolant leakage,
and correct if necessary.√√√√√
Replace coolant. Every 2 years
24*Moving parts and
cablesLubricate.√√√√
25*Drive select lever
safety system cableCheck operation and adjust or replace if neces-
sary.√√√ 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 320U37S61E0.book Page 7 Tuesday, June 2, 2009 10:33 AM

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8To install the panel
Place the panel in the original position and install
the bolts.
Panel F
To remove the panelPull outward on the areas shown.
To install the panelPlace the panel in its original position.
EBU23223Checking 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 panel A. (See page 8-9.)
2. Remove the spark plug cap.
1. Panel FU37S61E0.book Page 14 Tuesday, June 2, 2009 10:33 AM

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8 3. 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. Spark plug wrench
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EBU23328Engine 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. Remove panel F. (See page 8-9.)
3. 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 ten minutes until the oil set-
tles for an accurate reading.4. Remove the engine oil filler cap, and then
wipe the engine oil dipstick off with a clean
rag.5. Insert the dipstick into 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.1. Engine oil filler cap
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86. 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 into the oil filler hole, and
then tighten the engine oil filler cap.
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 8-9.)
3. Start the engine, warm it up for several min-
utes, and then turn it off.
4. Place an oil pan under the engine to collect
the used oil.
5. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase.1. Engine oil dipstick
2. Maximum level mark
3. Minimum level mark
1. Engine oil drain bolt
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TIPSkip steps 6–10 if the oil filter cartridge is not being
replaced.6. Remove panels D and E. (See page 8-9.)
7. Remove the oil filter cartridge with an oil filter
wrench.
TIPAn oil filter wrench is available at a nearby Yamaha
dealer.8. Apply a thin coat of engine oil to the O-ring of
the new oil filter cartridge.
1. Oil filter cartridge
1. Oil filter wrench
U37S61E0.book Page 19 Tuesday, June 2, 2009 10:33 AM