overheating YAMAHA GRIZZLY 450 2010 Owners Manual

6-5
64. 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.EBU20690Parking When parking the ATV, stop the engine, shift the
drive select lever into the park position, and then
turn the fuel cock to the “OFF” position.
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8-33
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. 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 filtercase. 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.EBU27081Cleaning the spark arrester Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the bolts.
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8-63
8 Engine 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.
U37S61E0.book Page 63 Tuesday, June 2, 2009 10:33 AM