YAMAHA GRIZZLY 550 2011 Owners Manual

8-41
8 8. Check the sponge material and replace it if
damaged.
9. Apply Yamaha foam air filter oil or other qual-
ity foam air filter oil to the sponge material.
TIPThe sponge material should be wet but not drip-
ping.10. Install the mesh and the sponge material into
the air filter case. 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 removed. This
will allow unfiltered air to enter the engine,
causing rapid engine wear and possibleengine damage. Additionally, operation
without the air filter element will affect the
fuel injection system with subsequent
poor performance and possible engine
overheating.
[ECB00761]
11. Insert the projections on the air filter case cov-
er into the holders on the air filter case, and
then install the air filter case cover by hooking
the holders onto the cover.
12. Place the hoses in their original position as
shown.1. Air filter case cover
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8-42
813. Install the panel.
TIPThe 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 throttle body 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.
EBU27812Cleaning the spark arrester Select a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the bolts.
2. Remove the tailpipe by pulling it out of the
muffler, and then remove the gasket.
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.
1. Hose
1
1. Bolt
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8-43
8 4. Check the gasket for damage, and replace it if
necessary.
5. Install the gasket, and then insert the tailpipe
into the muffler and align the bolt holes.
6. Install the bolts and tighten them to the speci-
fied torque.
7. Remove the purging bolt and its gasket.8. Start the engine and rev it up approximately
twenty times while momentarily creating ex-
haust system back pressure by blocking the
end of the muffler with a shop towel.
9. Stop the engine and allow the exhaust pipe to
cool.
10. Check the gasket for damage, and replace it if
necessary.
11. Install the purging bolt and its gasket, and
then tighten the bolt to the specified torque.
1. Tailpipe
2. Spark arrester
3. GasketTightening torque:
Tailpipe bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1. Purging bolt
2. Gasket
2
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8
WARNING
EWB02380Never run the engine in an enclosed area when
purging the spark arrester, otherwise it could
cause injury to the eyes, burns, carbon monox-
ide poisoning, possibly leading to death, and
start a fire.
Always let the exhaust system cool prior to
touching exhaust components.
Always wear eye protection, and make sure
no one is behind the ATV.
Make sure there are no combustible materi-
als in the area.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.
TIPIf water drains from the V-belt case after removing
the plug, have a Yamaha dealer check the ATV as
the water may affect other engine parts.EBU29700Adjusting 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. Tightening torque:
Purging bolt:
27 Nm (2.7 m·kgf, 20 ft·lbf)1. V-belt case drain plug
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8 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.
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).
4. Tighten the locknut.5. Slide the rubber cover to its original position.
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.EBU24071Adjusting 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 by a Yamaha dealer at the
intervals specified in the periodic maintenance and
lubrication chart.EBU29601Brakes Replacement of brake components requires pro-
fessional knowledge. Brake service should be per-
formed by a Yamaha dealer.
1. Rubber cover
2. Throttle cable free play adjusting bolt
3. Locknut
4. Throttle cable free play
2WD
4WD
3
2
1
4 (b)
(a)
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8
WARNING
EWB02571Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.EBU27470Checking the front and rear brake pads The front and rear brake pads must be checked for
wear at the intervals specified in the periodic main-
tenance and lubrication chart. Each brake pad is
provided with a wear indicator groove, which al-
lows you to check the brake pad wear without hav-
ing to disassemble the brake. If a brake pad has
worn to the point that the wear indicator groove has
almost disappeared, have a Yamaha dealer re-
place the brake pads as a set.TIPThe wheels need to be removed to check the
brake pads. (See page 8-64.)
Front brake
Rear brake1. Wear indicator groove
1. Wear indicator groove
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8
EBU27843Checking the rear brake hose protec-
tors The rear brake hose protectors must be checked
for wear at the intervals specified in the periodic
maintenance and lubrication chart. Each brake
hose protector is provided with a wear indicator. If
a protector wears to the point that its indicator be-
comes visible, have a Yamaha dealer replace the
protector.TIPThe wheels need to be removed to check the
brake hose protectors. (See page 8-64.)
EBU29840Checking the brake fluid level Insufficient brake fluid may allow air to enter the
brake system, possibly causing it to become inef-
fective.
Before riding, check that the brake fluid is above
the minimum level mark and replenish if neces-
sary. A low brake fluid level may indicate worn
brake pads and/or brake system leakage. If the
brake fluid level is low, be sure to check the brake
pads for wear and the brake system for leakage.1. Rear brake hose protector
2. Wear indicator
3. Protector is normal.
4. Protector is worn.
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8-48
8Front brake
Rear brakeObserve these precautions:

When checking the fluid level, make sure that
the top of the brake fluid reservoir is level.
Use only the recommended quality brake fluid,
otherwise the rubber seals may deteriorate,
causing leakage and poor braking performance.
Refill with the same type of brake fluid. Mixing
fluids may result in a harmful chemical reaction
and lead to poor braking performance.
Be careful that water does not enter the brake
fluid reservoir when refilling. Water will signifi-
cantly lower the boiling point of the fluid and may
result in vapor lock.
Brake fluid may deteriorate painted surfaces or
plastic parts. Always clean up spilled fluid imme-
diately.
As the brake pads wear, it is normal for the brake
fluid level to gradually go down. However, if the
brake fluid level goes down suddenly, have a
Yamaha dealer check the cause.
1. Minimum level mark
1. Minimum level mark
2WD
4WD
1
Recommended brake fluid:
DOT 4
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8
EBU24291Changing the brake fluid Have a Yamaha dealer change the brake fluid at
the intervals specified in the TIP after the periodic
maintenance and lubrication chart. In addition,
have the oil seals of the master cylinders and cali-
pers as well as the brake hoses replaced at the in-
tervals listed below or whenever they are damaged
or leaking.
Oil seals: Replace every two years.
Brake hoses: Replace every four years.EBU27772Checking the front and rear brake lever
free play The front and rear brake lever free play must be
checked at the intervals specified in the periodic
maintenance and lubrication chart. The brake le-
vers should have no free play as shown. If there is
free play, have a Yamaha dealer check the brake
system.Front brake
Rear brake
1. No brake lever free play
1. No brake lever free play
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8
EBU29072Adjusting the brake pedal free play The brake pedal free play must be adjusted at the
intervals specified in the periodic maintenance and
lubrication chart.TIP
Always perform this maintenance completely in
the following order whenever adjusting the rear
brake.
Before adjusting the brake pedal free play,
check the rear brake pads for wear.The brake pedal free play should measure 0.0–5.0
mm (0.00–0.20 in) as shown. If the free play is in-
correct, adjust it as follows.1. Remove panel H. (See page 8-10.)
2. Loosen the locknut.
3. Turn the brake pedal free play adjusting nut in
direction (a) to increase the free play, and in
direction (b) to decrease it.
1. Brake pedal free play
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