2012 YAMAHA GRIZZLY 450 engine overheat

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4
EBU17842Reverse indicator light“”
This indicator light comes on when the transmis-
sion is in the reverse position.
Furthermore, this indicator light flashes when the
engine is being raced for 10 seconds or more.TIPIf the indicator light flashes under any other circum-
stances or the speedometer does not show the
speed while riding, have a Yamaha dealer check
the speed sensor circuit.EBU17970Park indicator light “”
This indicator light comes on when the transmis-
sion is in the park position.EBU17920Coolant temperature warning light “”
This warning light comes on when the engine over-
heats. When this occurs during operation, stop the
engine as soon as it is safe to do so and allow it to
cool down for about 10 minutes.
NOTICEECB00010
The engine may overheat if the ATV is over-
loaded. In this case, reduce the load to spec-
ification.
Start the engine after making sure that the
warning light is out. Continuous use while
the warning light is on may cause damage to
the engine.EBU27543Electric Power Steering warning light “EPS ”
This warning light comes on when the key is turned
to “ON ”, and then goes off once the engine is start-
ed. If the warning light remains on or comes on af-
ter the engine is started, the EPS system may not
be working correctly. When this occurs, have a
Yamaha dealer check the EPS system. The electrical circuit of the warning light can be
checked by turning the key to “ON ”. If the warning
light does not come on, have a Yamaha dealer
check the electrical circuit.
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4
TIP
If the engine is stopped using the engine stop
switch and the key is in the “ON ” position, the
EPS warning light comes on to indicate that the
power assistance for the steering is not function-
ing.
If the steering load is too heavy (i.e., excessive
steering use when the ATV is traveling at a slow
speed), the power assist is reduced to protect
the EPS motor from overheating.EBU29621On-Command four-wheel-drive indicator “”,
On-Command differential gear lock
indicator “” and indicator light “DIFF.
LOCK”
The On-Command four-wheel-drive indicator “”
comes on when the On-Command four-wheel-
drive switch is set to the “4WD ” position.
The On-Command differential gear lock
indicator “” and the On-Command differential
gear lock indicator light “DIFF. LOCK ” come on
when the On-Command differential gear lock
switch is set to the “LOCK ” position.
TIP
Due to the synchronizing mechanism in the dif-
ferential gear case, the four-wheel-drive indica-
tor may not come on until the ATV starts moving.
When the On-Command differential gear lock
switch is set to “LOCK ”, the indicator “” and
the indicator light “DIFF. LOCK ” will flash until
the differential gear is locked. If the indicator and
the indicator light continue to flash, the differen-
tial is not locked. In this case, start moving to al-
low time for the differential to lock.
U1CT61E0.book Page 4 Wednesday, April 20, 2011 6:36 PM

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6
4. Check behind for people or obstacles, and
then release the brake pedal.
5. Open the throttle lever gradually and continue to watch to the rear while backing.
EBU20682Engine break-in TIP
For ATVs equipped with an odometer or an hour
meter, follow the figures given in km (mi) or the
figures given in hours.
For ATVs not equipped with an odometer or
hour meter, follow the figures given in hours.There is never a more important period in the life of
your engine than the first 320 km (200 mi) or 20
hours of riding. For this reason, you should read
the following material carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 320 km (200 mi) or 20
hours. The various parts in the engine wear and
polish themselves to the correct operating clear-
ances. During this period, prolonged full-throttle
operation or any condition that might result in en-
gine overheating must be avoided. 0
– 160 km (0 –100 mi) or 0 –10 hours
Avoid prolonged operation above 1/2 throttle. Vary
the speed of the ATV regularly. Do not operate it at
one set throttle position.
160– 320 km (100 –200 mi) or 10 –20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine freely, but do not use full throttle at any
time.
320 km (200 mi) or 20 hours and beyond
The ATV can now be operated normally.
NOTICEECB00220If any engine trouble should occur during the
engine break-in period, immediately have a
Yamaha dealer check the ATV.EBU20691Parking When parking the ATV, stop the engine, apply the
brake pedal, shift the drive select lever into the
park position, and then turn the fuel cock to the
“ OFF ” position.
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8-28
8
TIP
The radiator fan is automatically switched on or
off according to the coolant temperature in the
radiator.
If the engine overheats, see page 8-63 for fur-
ther instructions.EBU23605To 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 pressure
to escape before completely removing the cap.1. Place the ATV on a level surface.
2. Remove panels D and E. (See page 8-10.)
3. Place a container under the engine, and thenremove the coolant drain bolt and its gasket.
(Use a trough or a similar object as shown to
prevent coolant from spilling on the footrest.)
1. Coolant drain bolt
2. Gasket
1. Trough
12
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8-33
88. 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. 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.
NOTICE: Make sure that the air filter ele-
ment is properly seated in the air filter case. Never operate the engine with the air
filter element removed. This will allow un-
filtered air to enter the engine, causing rap-
id engine wear and possible engine
damage. Additionally, operation without
the air filter element will affect carburetor
jetting with subsequent poor performance
and possible engine overheating.
[ECB00461]
12. Install the seat.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 carburetor fittings and the rubber joint
manifold fittings for an air-tight seal. Tighten all fit-
tings securely to avoid the possibility of unfiltered
air entering the engine.EBU27082Cleaning the spark arrester Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester. 1. Remove the tailpipe bolts.
U1CT61E0.book Page 33 Wednesday, April 20, 2011 6:36 PM

8-63
8Engine overheating
WARNING
EWB02290Wait 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 rec-
ommended 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.
U1CT61E0.book Page 63 Wednesday, April 20, 2011 6:36 PM