2007 YAMAHA GRIZZLY 350 engine

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8
CAUTION:ECB00300
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 thecrankcase.
10. 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.
11. Turn the engine off, wait at least ten minutes,
and then check the oil level and correct it if
necessary.
EBU28570Final 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.NOTE:The final gear oil level must be checked on a coldengine.
2. Remove the final gear oil filler bolt, and then
check the oil level in the final gear case.NOTE:The oil level should be at the brim of the filler hole. Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter cartridge replacement:
2.20 L (2.33 US qt) (1.94 Imp.qt)
With oil filter cartridge replacement:
2.30 L (2.43 US qt) (2.02 Imp.qt)
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8-15
8 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. Install the oil filler bolt, and then tighten it to the
specified torque.To change the final gear oil
1. Remove the engine guard and the final gear
case guard by removing the bolts.
2. Place the ATV on a level surface.
3. Place an oil pan under the final gear case to
collect the used oil.
4. Remove the final gear oil filler bolt and the fi-
nal gear oil drain bolt to drain the oil from the
final gear case.
1. Final gear oil filler bolt
2. Correct oil level
3. Final gear oilTightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Engine guard
2. Final gear case guard
3. Bolt
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8
CAUTION:ECB00420Be sure no foreign material enters the finalgear case.
7. Install the oil filler bolt, and then tighten it to the
specified torque.
8. Check the final gear case for oil leakage. If oil
is leaking, check for the cause.
9. Install the engine guard and the final gear
case guard by installing the bolts, and then
tightening them to the specified torques.
EBU23421Differential gear oil The 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 level
1. Place the ATV on a level surface.NOTE:The differential gear oil level must be checked ona cold engine.
2. Remove the differential gear oil filler bolt, and
then check the oil level in the differential gear
case. Tightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
Tightening torques:
Engine guard bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Final gear case guard bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
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8-21
8 4. Pull off the lock plate, and then remove the
sponge material from the air filter element
frame.5. Wash the sponge material gently but thor-
oughly in solvent.
WARNING
EWB01940Always use parts cleaning solvent to clean the
sponge material. Never use low-flash-point
solvents or gasoline to clean the sponge mate-
rial because the engine could catch fire or ex-plode.
6. Squeeze the excess solvent out of the sponge
material and let it dry.
1. Air filter element
1. Air filter element frame
2. Sponge material
3. Air filter element lock plate
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8
CAUTION:ECB00440Do not twist the sponge material when squeez-ing it.
7. Check the sponge material and replace it if
damaged.
8. Apply a quality foam air filter oil to the sponge
material.NOTE:The sponge material should be wet but not drip-ping.
9. Pull the sponge material over the air filter ele-
ment frame, and then install the lock plate.
10. Insert the air filter element into the air filter
case, and then install the air filter case cover
by hooking the holders onto the air filter case.
11. Install the seat.NOTE:The air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the ATV is operated in extremely dusty ar-
eas. Each time the air filter element maintenance
is performed, 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 jointmanifold fittings for an air-tight seal. Tighten all fit-
tings securely to avoid the possibility of unfiltered
air entering the engine.CAUTION:ECB00460
Make sure that the air filter element is prop-
erly seated in the air filter case.
Never operate the engine with the air filter el-
ement removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addition-
ally, operation without the air filter element
will affect carburetor jetting with subsequent
poor performance and possible engine over-heating.EBU27080Cleaning 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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8-23
8 2. Remove the tailpipe by pulling it out of the
muffler.
3. Tap the tailpipe lightly, and then use a wire
brush to remove any carbon deposits from the
spark arrester portion of the tailpipe and inside
of the tailpipe housing.4. Insert the tailpipe into the muffler and align the
bolt holes.
5. Install and tighten the bolts.
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 totouching exhaust components.
1. Bolt
2. Tailpipe
1. Tailpipe
2. Spark arrester
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8
EBU23920V-belt cooling duct check hose If dust or water collects in the V-belt cooling duct
check hose, remove the hose and clean it.EBU23930V-belt case drain plug After riding in water deep enough to allow it to en-
ter the V-belt case, remove this plug to drain the
water from the case.NOTE:If water drains from the V-belt case after removing
the plug, have a Yamaha dealer check the ATV asthe water may affect other engine parts.
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.
1. V-belt cooling duct check hose (left front side of ATV)
1. V-belt case drain plug
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8
CAUTION:ECB00480The 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 ordamage 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.NOTE:A diagnostic tachometer is needed to make thisadjustment.
1. Start the engine and warm it up.NOTE:The engine is warm when it quickly responds to thethrottle.
2. Attach the tachometer to the spark plug lead.
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).
NOTE:If the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make theadjustment.1. Throttle stop screwEngine idling speed:
1450–1550 r/min
U4S260E0.book Page 25 Tuesday, October 3, 2006 1:53 PM