2009 YAMAHA GRIZZLY 450 engine overheat

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4
EBU17813Indicator lights and warning light 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 checkthe speed sensor circuit.EBU17860Neutral indicator light“”
This indicator light comes on when the transmis-
sion is in the neutral 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.
1. On-Command differential gear lock indicator light “DIFF.
LOCK”
2. Low-range indicator light “L”
3. High-range indicator light “H”
4. Neutral indicator light “N”
5. Reverse indicator light “R”
6. Park indicator light “P”
7. On-Command four-wheel-drive/differential gear lock
indicator“”/“”
8. Coolant temperature warning light“”U37S60E0.book Page 2 Thursday, June 5, 2008 6:51 PM

6-5
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.
WARNING
EWB00720Improper operation in reverse could make you
hit an obstacle or even a person behind you,
resulting in serious injury. When you shift into
reverse, make sure there are no people or ob-
stacles behind you. When it is safe to proceed,go slowly.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 orhour 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 aYamaha dealer check the ATV.
U37S60E0.book Page 5 Thursday, June 5, 2008 6:51 PM

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NOTICEECB00401
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.TIP
The radiator fan is automatically switched on or
off according to the coolant temperature in the
radiator.
If the engine overheats, see page 8-61 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.) Coolant reservoir capacity (up to the maximum
level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
U37S60E0.book Page 28 Thursday, June 5, 2008 6:51 PM

8-62
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.
U37S60E0.book Page 62 Thursday, June 5, 2008 6:51 PM