2008 YAMAHA GRIZZLY 660 engine

8-27
8
NOTE:The coolant level must be checked on a cold en-
gine since the level varies with engine tempera-ture.
2. Check the coolant level in the coolant reser-
voir.NOTE:The coolant should be between the minimum andmaximum level marks.3. If the coolant is at or below the minimum level
mark, remove panel D. (See page 8-9.)
4. Remove the reservoir cap, add coolant or dis-
tilled water to the maximum level mark, install
the reservoir cap, and then install the panel.
CAUTION:ECB00401
If coolant is not available, use distilled water
or soft tap water instead. Do not use hard wa-
ter or salt water since it is harmful to the en-
gine.
If water has been used instead of coolant, re-
place it with coolant as soon as possible,
otherwise the cooling system will not be pro-
tected against frost and corrosion.
If water has been added to the coolant, have
a Yamaha dealer check the antifreeze con-
tent of the coolant as soon as possible, oth-
erwise the effectiveness of the coolant willbe reduced.
1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
Coolant reservoir capacity (up to the maximum
level mark):
0.30 L (0.32 US qt) (0.26 Imp.qt)
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8
NOTE:
The radiator fan is automatically switched on or
off according to the coolant temperature in the
radiator.
If the engine overheats, see page 8-57 for fur-ther instructions.EBU23602To change the coolant
WARNING
EWB01890Wait 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 place a thick rag over the cap
when opening. Allow any remaining pressureto escape before completely removing the cap.
1. Place the ATV on a level surface.
2. Remove panels E and F. (See page 8-9.)
3. Place a container under the engine, and then
remove the coolant drain bolt. (Use a trough
or a similar object as shown to prevent coolant
from spilling on the footrest.)
4. Remove the front carrier and panel C. (See
page 8-9.)
1. Coolant drain bolt
1. Trough
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8-30
813. Pour the recommended coolant into the radia-
tor until it is full.
CAUTION:ECB00401
If coolant is not available, use distilled water
or soft tap water instead. Do not use hard wa-
ter or salt water since it is harmful to the en-
gine.
If water has been used instead of coolant, re-
place it with coolant as soon as possible,
otherwise the cooling system will not be pro-
tected against frost and corrosion.

If water has been added to the coolant, have
a Yamaha dealer check the antifreeze con-
tent of the coolant as soon as possible, oth-
erwise the effectiveness of the coolant willbe reduced.
14. Install the radiator cap, start the engine, let it
idle for several minutes, and then turn it off.
15. Remove the radiator cap to check the coolant
level in the radiator. If it is low, add sufficient
coolant until it reaches the top of the radiator,
and then install the radiator cap.
16. Start the engine, and then check for coolant
leakage.
NOTE:If any leakage is found, have a Yamaha dealercheck the cooling system.
17. Install the panels and the front carrier.EBU23660Cleaning 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. Antifreeze/water mixture ratio:
1:1
Recommended antifreeze:
High-quality ethylene glycol antifreeze con-
taining corrosion inhibitors for aluminum en-
gines
Coolant quantity:
Radiator capacity (including all routes):
1.80 L (1.90 US qt) (1.58 Imp.qt)
Coolant reservoir capacity (up to the maxi-
mum level mark):
0.30 L (0.32 US qt) (0.26 Imp.qt)
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8-32
84. 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. Unlock.
1. Air filter element frame
2. Sponge material
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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.
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.NOTE:Be sure to connect the breather hose to the air filtercase cover.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 joint
manifold fittings for an air-tight seal. Tighten all fit-
tings securely to avoid the possibility of unfilteredair entering the engine.1. Breather hose
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8-34
8
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.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.
1. Bolt
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8-35
8 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.
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.
1. Tailpipe
2. Spark arrester
1. V-belt cooling duct check hose (left front side of ATV)
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8
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.
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.EBU24010Adjusting 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. Remove panel D. (See page 8-9.)
3. Attach the tachometer to the spark plug lead.
1. V-belt case drain plugU23D60E0.book Page 36 Thursday, March 15, 2007 7:59 PM