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8
NOTE:Be sure to wipe off spilled oil on any parts after theengine and exhaust system have cooled down.CAUTION:ECB00300In 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.
EBU23383Final 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. 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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NOTE: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. Install the oil filler bolt, and then tighten it to the
specified torque.To change the final gear oil
1. Place the ATV on a level surface.
2. Remove the final gear case guard by remov-
ing the bolts.
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
2. Final gear oil filler bolt
3. Correct oil levelTightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Final gear case guard
2. Bolt
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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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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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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:ECB00460Make 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