YAMAHA GRIZZLY 350 2008 Owners Manual

8-17
8 5. Install the drain bolt, and then tighten it to the
specified torque.
6. Refill with the recommended final gear oil to
the brim of the filler hole as shown.
CAUTION:ECB00420Be sure no foreign material enters the finalgear case.
7. Install the oil filler bolt, and then tighten it to the
specified torque.
1. Final gear oil drain boltTightening torque:
Final gear oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Final gear oil
2. Final gear oil filler bolt
3. Correct oil levelRecommended final gear oil:
See page 10-1.

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88. Check the final gear case for oil leakage. If oil
is leaking, check for the cause.
9. Install the final gear case guard by installing
the bolts and tightening them to the specified
torque.
EBU23433Changing the differential gear oil (4WD
model)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 must be
changed as follows at the intervals specified in the
periodic maintenance and lubrication chart.
1. Place the ATV on a level surface.
2. Place an oil pan under the differential gear
case to collect the used oil.3. Remove the differential gear oil filler bolt and
the differential gear oil drain bolt to drain the
oil from the differential gear case. Tightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
Tightening torque:
Final gear case guard bolt:
16 Nm (1.6 m·kgf, 11 ft·lbf)
1. Differential gear oil filler bolt

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8 4. Install the drain bolt, and then tighten it to the
specified torque.
5. Refill with the specified amount of the recom-
mended differential gear oil.
NOTE:
Do not exceed the specified differential gear oil
quantity when filling. Overfilling will cause the oil
to seep out of the breather hose during and after
riding.

The differential gear case capacity is greater
than the recommended oil quantity, therefore
the oil level cannot be accurately checked fromthe oil filler hole.CAUTION:ECB00410Be sure no foreign material enters the differen-tial gear case.
6. Install the oil filler bolt, and then tighten it to the
specified torque.
7. Check the differential gear case for oil leak-
age. If oil is leaking, check for the cause.
1. Differential gear oil drain boltTightening torque:
Differential gear oil drain bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Recommended differential gear oil:
See page 10-1.
Oil quantity:
YFM350FWA 0.35 L (0.37 US qt) (0.31
Imp.qt)
Tightening torque:
Differential gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)

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8
EBU23644Cleaning the air filter element The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean the air filter element more
frequently if you are riding in unusually wet or dusty
areas.NOTE:There 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 4-15.)
3. Remove the air filter case cover by unhooking
the air filter case cover holders.
4. Pull the air filter element out of the air filter
case.1. Air filter case check hose
1. Air filter case cover holder
2. Air filter case cover

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8 5. Pull off the air filter element lock plate, and
then remove the sponge material from the air
filter element frame.6. 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.
7. 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.
8. Check the sponge material and replace it if
damaged.
9. Apply a quality foam air filter oil to the sponge
material.NOTE:The sponge material should be wet but not drip-ping.
10. Pull the sponge material over the air filter ele-
ment frame, and then install the lock plate.11. 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.
12. 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 joint
manifold fittings for an air-tight seal. Tighten all fit-
tings securely to avoid the possibility of unfilteredair 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

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8 will affect carburetor jetting with subsequent
poor performance and possible engine over-
heating.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-
1. V-belt cooling duct check hose (left front side of ATV)
1. V-belt case drain plug

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8sional knowledge and experience. The adjustment
described in the following section, however, may
be performed by the owner as part of routine main-
tenance.
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).
1. Throttle stop screwEngine idling speed:
1450–1550 r/min

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8
NOTE:If the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make theadjustment.EBU24044Adjusting 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.NOTE:The engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle ca-ble free play.
1. Loosen the locknut.
2. 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).3. Tighten the locknut.
EBU24060Valve clearance The 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. Locknut
2. Throttle cable free play adjusting bolt
3. Throttle cable free play

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8
EBU24070Adjusting the drive select lever safety
system cable The drive select lever safety system cable stretch-
es with use, which can result in improper function.
Therefore, the safety system cable should be
checked and adjusted at the intervals specified in
the periodic maintenance and lubrication chart.EBU24120Checking the front brake pads and rear
brake shoes The front brake pads and the rear brake shoes
must be checked for wear at the intervals specified
in the periodic maintenance and lubrication chart.EBU24171Front brake pads
Check each front brake pad for damage and mea-
sure the lining thickness. If a brake pad is dam-
aged or if the lining thickness is less than 1.0 mm
(0.04 in), have a Yamaha dealer replace the brake
pads as a set.
NOTE:The wheels need to be removed to check thebrake pads. (See page 8-38.)EBU24180Rear brake shoes
The rear brake is provided with a wear indicator,
which allows you to check the brake shoe wear
without having to disassemble the brake. To check
the brake shoe wear, check the position of the
wear indicator while applying the brake. If a brake1. Brake pad
2. Lining thickness