engine YAMAHA GRIZZLY 250 2010 Owner's Guide

8-7
8
14 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√
15Engine oil filter ele-
mentClean or replace if necessary.√√√
16 Engine oil strainerClean.√√√
17 Final gear oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√√
18*Moving parts and
cablesLubricate.√√√√
19*Drive select lever
safety system cableCheck operation and adjust or replace if neces-
sary.√√√
20*Throttle lever hous-
ing and cableCheck operation and correct if necessary.
Check throttle cable free play and adjust if neces-
sary.
Lubricate throttle lever housing and cable.√√√√√
21*Front and rear brake
switchesCheck operation and correct if necessary.√√√√√
22*Lights and switchesCheck operation and correct if necessary.
Adjust headlight beams.√√√√√ 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 320U1P065E0.book Page 7 Monday, August 31, 2009 1:10 PM

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EBU23213Checking 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 cap
1. Spark plug wrench
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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.
3. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.
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. Specified spark plug:
NGK/DR7EA
1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
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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 specified
torque as soon as possible.3. Install the spark plug cap.EBU2329FEngine oil and oil filter element The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element cleaned at the intervals speci-
fied 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 ten minutes until the oil set-
tles for an accurate reading.3. Remove the engine oil filler cap, and then
wipe the engine oil dipstick off with a clean
rag.
4. 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.
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)
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5. 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]
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.To change the engine oil (with or without oil fil-
ter element cleaning)
1. Place the ATV on a level surface.
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Place an oil pan under the engine to collect
the used oil.
4. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase. NOTICE: When remov-
ing the engine oil drain bolt, the compres-
sion spring, oil strainer and O-ring will fall
out. Take care not to lose these parts.
[ECB00311]
1. Engine oil filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Minimum level markU1P065E0.book Page 12 Monday, August 31, 2009 1:10 PM

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TIPSkip steps 5–11, 16, and 17 if the oil filter element
is not being cleaned.5. Remove the footboard by removing the bolts.6. Fully loosen the brake pedal free play adjust-
ing nut, and push the brake pedal downward.1. Engine oil drain bolt
2. O-ring
3. Compression spring
4. Oil strainer
1. Footboard
2. Bolt
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8 12. Install the oil strainer, the compression spring,
a new O-ring and the engine oil drain bolt, and
then tighten the engine oil drain bolt to the
specified torque. NOTICE: Before installing
the engine oil drain bolt, be sure to install
the O-ring, compression spring and oil
strainer.
[ECB00321]
13. Refill with the specified amount of the recom-
mended engine oil, and then install and tight-
en the engine oil filler cap.
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.
Make sure that no foreign material enters the
crankcase.14. 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.
15. Turn the engine off, wait at least ten minutes,
and then check the oil level and correct it if
necessary.
16. Install the footboard by installing the bolts, and
then tighten them to the specified torques. Tightening torque:
Engine oil drain bolt:
43 Nm (4.3 m·kgf, 31 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element removal:
1.50 L (1.59 US qt, 1.32 Imp.qt)
With oil filter element removal:
1.60 L (1.69 US qt, 1.41 Imp.qt)
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810. Pull the sponge material over the air filter ele-
ment.
11. Insert the air filter element assembly into the
air filter case, and then install the air filter case
cover by hooking the holders. NOTICE: Make
sure that the air filter element is properly
seated in the air filter case. Never operate
the engine with the air filter element re-
moved. This will allow unfiltered air to en-
ter the engine, causing rapid engine wear
and possible engine damage. Additionally,
operation without the air filter element will
affect carburetor jetting with subsequent
poor performance and possible engine
overheating.
[ECB00461]
12. Install the seat.TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned more often if the
ATV is operated in extremely dusty areas. Each
time the air filter element maintenance is per-
formed, check the air inlet of the air filter case for
obstructions. Check the air filter case rubber joint
to the carburetor fittings and the rubber joint mani-
fold fittings for an air-tight seal. Tighten all fittings
securely to avoid the possibility of unfiltered air en-
tering the engine.EBU27081Cleaning the spark arrester Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the bolts.
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WARNING
EWB02340Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components.EBU23940Adjusting the carburetor The carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the peri-
odic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. Therefore,
most carburetor adjustments should be left to a
Yamaha dealer, who has the necessary profes-
sional knowledge and experience. The adjustment
described in the following section, however, may
be performed by the owner as part of routine main-
tenance.
NOTICEECB00480The 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.EBU24000Adjusting the engine idling speed The engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance and lubrica-
tion chart.TIPA diagnostic tachometer is needed to make this
adjustment.1. Start the engine and warm it up.TIPThe engine is warm when it quickly responds to the
throttle.2. Attach the tachometer to the spark plug lead.
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8 3. Check the engine idling speed and, if neces-
sary, adjust it to specification by turning the
throttle stop screw at the carburetor. To in-
crease the engine idling speed, turn the throt-
tle stop screw in direction (a), and to decrease
it, turn the screw in direction (b).
TIPIf the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment.EBU24045Adjusting the throttle cable free play The throttle cable free play should be checked
and, if necessary, adjusted at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
The throttle cable free play should measure 3.0–
5.0 mm (0.12–0.20 in) at the throttle lever. Period-
ically check the throttle cable free play and, if nec-
essary, adjust it as follows.TIPThe engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle ca-
ble free play.1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle cable free play, turn
the throttle cable free play adjusting bolt in di-
rection (a). To decrease the throttle cable free
play, turn the adjusting bolt in direction (b).
1. Throttle stop screwEngine idling speed:
1400–1500 r/min
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