2010 YAMAHA GRIZZLY 450 check engine

6-1
6
EBU19880
OPERATION
EBU19901Read the Owner’s Manual carefully before riding
the ATV. If there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWB00631Read the Owner’s Manual carefully to become
familiar with all controls in order to help pre-
vent any loss of control, which could cause an
accident or injury.EBU20054Starting a cold engine NOTICEECB00150See the “Engine break-in” section on page 6-5
prior to operating the engine for the first time.1. Turn the fuel cock to “ON”.
2. Turn the key to “ON” and the engine stop
switch to“”.3. Shift the drive select lever into the neutral or
park position. The corresponding indicator
light should come on. If the indicator light does
not come on, have a Yamaha dealer check
the electrical circuit.
TIPThe engine can be started under the following con-
ditions:
The drive select lever is in the neutral or park po-
sition.
The rear brake lever is applied with the drive se-
lect lever in any position. However, it is recom-
mended to shift into the neutral or park position
before starting the engine.4. Use the starter (choke) in reference to the fig-
ure:
Position (1):
Cold engine start with ambient temperature
below 5 °C (40 °F).
Position (2):
Cold engine start with ambient temperature
between 0 °C (30 °F) and 30 °C (90 °F).
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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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7-8
7 an overturn. Never attempt stunts, such as
wheelies or jumps. Don’t try to show off.
[EWB01481]Modifications and accessories
Never modify this ATV through improper installa-
tion or use of accessories or other modification. All
parts and accessories added to this ATV should be
genuine Yamaha or equivalent components de-
signed for use on this ATV and should be installed
and used according to instructions. If you have
questions, consult an authorized ATV dealer.
WARNING! Operating this ATV with improper
modifications may cause changes in handling
which in some situations could lead to an acci-
dent.
[EWB01491]
Exhaust system
WARNING
EWB01501
Dry grass or brush or other combustible ma-
terial accumulated around the engine area
could catch fire. Do not operate, idle, or park
the ATV in dry grass or other dry ground cov-
er. Keep the engine area free of dry grass,
brush, or other combustible material.
Someone touching the exhaust system dur-
ing or after operation could be burned. Do
not touch the hot exhaust system. Do not
park the ATV in a place where others might
be likely to touch it.The muffler and other engine parts become ex-
tremely hot during operation and remain hot after
the engine has stopped. To reduce the risk of fire
during operation or after leaving the ATV, do not let
brush, grass and other materials collect under the
vehicle, near the muffler or exhaust pipe, or next to
other hot parts. Check under the vehicle after op-
erating in areas where combustible materials may
have collected. Do not idle or park the vehicle in
long dry grass or other dry ground cover.
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7-16
7 remount, following the procedure described in the
Owner’s Manual. WARNING! Stalling, rolling
backwards or improperly dismounting while
climbing a hill could result in ATV overturning.
If you cannot control the ATV, dismount imme-
diately on the uphill side.
[EWB01802]
RIDING DOWNHILL
WARNING
EWB01621Going down a hill improperly could cause
overturns or loss of control. Always follow
proper procedures for going down hills as de-
scribed in this Owner’s Manual.

Always check the terrain carefully before
you start down any hill.
Never operate the ATV on hills too steep for
the ATV or for your abilities. The ATV can
overturn more easily on extremely steep hills
than on level surfaces or small hills.
Shift your weight backward and to the up
side of the hill.
Never go down a hill at high speed.
Avoid going down a hill at an angle that
would cause the ATV to lean sharply to one
side. Go straight down the hill where possi-
ble.
Improper braking can cause the wheels on
the uphill side to come off the ground or
cause loss of traction. Apply brakes gradual-
ly. If in “2WD”, apply only the rear brake.When riding your ATV downhill, shift your weight
as far to the rear and uphill side of the ATV as pos-
sible. Move back on the seat and sit with your arms
straight. Engine compression will do most of the
braking for you. For maximum engine compres-
sion braking effect, select the low-range position
and change to “4WD” before beginning to descend
the hill.
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8-3
8
EBU21743Periodic maintenance chart for the emission control system TIP
For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should be followed.
Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,
data and technical skills.NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320
1*Fuel lineCheck fuel hoses for cracks or other damage, and
replace if necessary.√√√
2 Spark plugCheck condition and clean, regap, or replace if
necessary.√√√√√
3*ValvesCheck valve clearance and adjust if necessary.√ √√√
4*CarburetorCheck starter (choke) operation and correct if nec-
essary.
Check engine idling speed and adjust if neces-
sary.√√√√
5*Crankcase breather
systemCheck breather hose for cracks or other damage,
and replace if necessary.√√√
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8-7
8
16*Engine mountCheck for cracks or other damage, and replace if
necessary.√√√
17*Axle bootsCheck for cracks or other damage, and replace if
necessary.√√√√√
18 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√
19Engine oil filter car-
tridgeReplace.√√√
20*Engine oil strainerClean.√√√
21 Differential gear oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√√
22 Final gear oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√√√
23 Cooling systemCheck coolant level and ATV for coolant leakage,
and correct if necessary.√√√√√
Replace coolant. Every 2 years
24*Moving parts and
cablesLubricate.√√√√
25*Drive select lever
safety system cableCheck operation and adjust or replace if neces-
sary.√√√ NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320U37S61E0.book Page 7 Tuesday, June 2, 2009 10:33 AM

8-14
8To install the panel
Place the panel in the original position and install
the bolts.
Panel F
To remove the panelPull outward on the areas shown.
To install the panelPlace the panel in its original position.
EBU23223Checking the spark plug The spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug
1. Remove panel A. (See page 8-9.)
2. Remove the spark plug cap.
1. Panel FU37S61E0.book Page 14 Tuesday, June 2, 2009 10:33 AM

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8 3. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s tool
kit.To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
TIPIf the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.
1. Spark plug cap
1. Spark plug wrench
U37S61E0.book Page 15 Tuesday, June 2, 2009 10:33 AM