2015 YAMAHA GRIZZLY 550 engine

8-41
8
6. Wash the sponge material gently, but thor-
oughly, in solvent. WARNING! Always use
parts cleaning solvent to clean the sponge
material. Never use low-flash-point sol-
vents or gasoline to clean the sponge ma-
terial because the engine could catch fire
or explode.
[EWB01942]
7. Squeeze the excess solvent out of the sponge material and let it dry. NOTICE: Do
not twist the sponge material when
squeezing it.
[ECB00442]
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 en-
gine with the air filter element removed.
This will allow unfiltered air to enter the en-
gine, causing rapid engine wear and pos-
sible engine damage. Additionally,
operation without the air filter element will
affect the fuel injection system with subse-
quent poor performance and possible en-
gine overheating.
[ECB00762]
11. Insert the projections on the air filter case cover into the holders on the air filter case,
and then install the air filter case cover by
hooking the holders onto the cover.
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8-42
812. Place the hoses in their original position as
shown. 13. 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 areas. Each time the air filter element main-
tenance 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 rub-
ber joint manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU27814Cleaning the spark arresterSelect a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the tailpipe bolts.
1. Air filter case cover
1. Hose
1
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8-44
88. 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.
WARNING
EWB02381Never 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. EBU23932V-belt case drain plugAfter riding in water deep enough to allow it to en-
ter the V-belt case, remove the V-belt case drain
plug to drain the water from the case.
1. Purging bolt
2. Gasket
2
Tightening torque:
Purging bolt:27 Nm (2.7 m·kgf, 20 ft·lbf)
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8-45
8
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. EBU29703Adjusting the throttle lever free playThe throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 3.0–5.0
mm (0.12–0.20 in) as shown. Periodically check
the throttle lever free play and, if necessary, adjust
it as follows.1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turn
the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover to its original position.1. V-belt case drain plug
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
2WD
4WD
3
2
1
4
(b)
(a)
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8-46
8
EBU24061Valve clearanceThe 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.EBU24072Adjusting the drive select lever safety
system cableThe 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.EBU29602BrakesReplacement of brake components requires pro-
fessional knowledge. Brake service should be
performed by a Yamaha dealer.
WARNING
EWB02572Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident. EBU27471Checking the front and rear brake padsThe front and rear brake pads must be checked
for wear at the intervals specified in the periodic
maintenance and lubrication chart. Each brake
pad is provided with a wear indicator groove,
which allows you to check the brake pad wear
without having to disassemble the brake. If a
brake pad has worn to the point that the wear in-
dicator groove has almost disappeared, have a
Yamaha dealer replace the brake pads as a set.TIPThe wheels need to be removed to check the
brake pads. (See page 8-64.)
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8-67
8
EBU27695Troubleshooting chartsStarting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
Operate the electric starter.4. Compression
There is compression.
There is no compression.
The engine does not start.
Have a Yamaha dealer check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug. Have a Yamaha dealer check the ATV.
The engine does not start.
Check the compression.
DryWet
Operate the electric starter.
Have a Yamaha dealer check the ATV.
The engine does not start.
Check the ignition.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
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8-68
8Engine overheating
WARNING
EWB02291Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap. TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the
recommended coolant as soon as possible. Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer check
and repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
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9-1
9
EBU25861
CLEANING AND STORAGE
EBU25882CleaningFrequent, thorough cleaning of your ATV will not
only enhance its appearance but will improve its
general performance and extend the useful life of
many components.1. Before cleaning the ATV: a. Block off the end of the exhaust pipe toprevent water entry. A plastic bag and
strong rubber band may be used.
b. Make sure the spark plug and all filler caps are properly installed.
2. If the engine case is excessively greasy, apply degreaser with a paint brush. Do not apply
degreaser to the wheel axles.
3. Rinse the dirt and degreaser off with a garden hose. Use only enough pressure to do the
job. WARNING! Wet brakes may have re-
duced stopping ability, increasing the
chance of an accident. Test the brakes af-
ter washing. Apply the brakes several
times at slow speeds to let friction dry out
the linings.
[EWB02312]
NOTICE: Excessive wa-
ter pressure may cause water seepage and deterioration of wheel bearings,
brakes, transmission seals and electrical
devices. Many expensive repair bills have
resulted from improper high-pressure de-
tergent applications such as those avail-
able in coin-operated car washers.
[ECB00712]
4. Once most of the dirt has been hosed off,
wash all surfaces with warm water and mild,
detergent-type soap. An old toothbrush or
bottle brush is handy for hard-to-reach pla-
ces.
5. Rinse the ATV off immediately with clean wa- ter and dry all surfaces with a chamois, clean
towel or soft absorbing cloth.
6. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
7. Automotive type wax may be applied to all painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
abrasives which may mar the paint or protec-
tive finish. When finished cleaning, start the
engine and let it idle for several minutes.
U2LB61E0.book Page 1 Friday, February 21, 2014 3:03 PM