2010 YAMAHA GRIZZLY 450 engine

4-16
4 doctor immediately. If gasoline spills on your
skin, wash with soap and water. If gasoline
spills on your clothing, change your clothes.
NOTICEECB00070Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system.Your Yamaha engine has been designed to use
regular unleaded gasoline with a research octane
number of 91 or higher. If knocking (or pinging) oc-
curs, use a gasoline of a different brand. Use of un-
leaded fuel will extend spark plug life and reduce
maintenance costs.EBU18820Fuel cock The fuel cock supplies fuel from the tank to the car-
buretor while also filtering it.
The fuel cock lever positions are explained as fol-
lows and shown in the illustrations.OFF
With the fuel cock lever in this position, fuel will not
flow. Always turn the fuel cock lever to this position
when the engine is not running.
1. Arrow mark pointing to “OFF”
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4-17
4ON
With the fuel cock lever in this position, fuel flows
to the carburetor. Turn the fuel cock lever to this
position when starting the engine and riding.RES
This indicates reserve. With the fuel cock lever in
this position, the fuel reserve is made available.
Turn the fuel cock lever to this position if you run
out of fuel while riding. When this occurs, refuel as
soon as possible and be sure to turn the fuel cock
lever back to “ON”!
EBU18850Starter (choke)“” Starting a cold engine requires a richer air-fuel mix-
ture, which is supplied by the starter (choke).
Move the starter (choke) in direction (a) to turn on
the starter (choke).
1. Arrow mark pointing to “ON”
1. Arrow mark pointing to “RES”
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4-18
4 Move the starter (choke) in direction (b) to turn off
the starter (choke).
See the “Starting a cold engine” section on page
6-1 for proper operation.
EBU18881Seat To remove the seat
Pull the seat lock lever upward and pull up the seat
at the rear.To install the seat
Insert the projections on the front of the seat into
the seat holders and push down on the seat at the
rear. Make sure that the seat is securely fitted.1. Starter (choke)“”
1. Seat
2. Seat lock lever
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4-23
4
EBU19182Auxiliary DC jack The auxiliary DC jack is located at the front right
side of the ATV. The auxiliary DC jack can be used
for suitable work lights, radios, etc. The auxiliary
DC jack should only be used when the engine is
running and the light switch is set to “OFF”.
1. Set the light switch to “OFF”.
2. Start the engine. (See page 6-1.)
3. Open the auxiliary DC jack cap, and then in-
sert the accessory power plug into the jack.4. When the auxiliary DC jack is not being used,
cover it with the cap.
NOTICEECB00120
Do not use accessories requiring more than
the above maximum capacity. This may
overload the circuit and cause the fuse to
blow.
If accessories are used without the engine
running or with the headlights turned on, the
battery will lose its charge and engine start-
ing may become difficult.
Do not use an automotive cigarette lighter or
other accessories with a plug that gets hot
because the jack can be damaged.
1. Auxiliary DC jack cap
2. Auxiliary DC jack
1
2
Maximum rated capacity for the auxiliary DC
jack:
DC 12 V, 10 A (120 W)
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5-1
5
EBU19201
PRE-OPERATION CHECKS
EBU19224Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00481Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer.Before using this vehicle, check the following points:
ITEM ROUTINE PAGE
FuelCheck fuel level in fuel tank, and add recommended fuel if neces-
sary.
Check fuel line for leakage. Correct if necessary.4-14, 5-3
Engine oilCheck oil level in engine, and add recommended oil to specified lev-
el if necessary.
Check ATV for oil leakage. Correct if necessary.5-3, 8-17
Final gear oilCheck ATV for oil leakage. Correct if necessary. 5-3, 8-21
Differential gear oilCheck ATV for oil leakage. Correct if necessary. 5-3, 8-24
CoolantCheck coolant level in reservoir, and add recommended coolant to
specified level if necessary.
Check cooling system for leakage. Correct if necessary.5-3, 8-26
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5-3
5
EBU19541Fuel Make sure that there is sufficient fuel in the tank.
(See page 4-14.)EBU19560Engine oil Make sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-17.)EBU19590Final gear oil Make sure that the final gear oil is at the specified
level. Add oil as necessary. (See page 8-21.)EBU19600Differential gear oil Make sure that the differential gear oil is at the
specified level. Add oil as necessary. (See page
8-24.)EBU19631Coolant Make sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-26.)
TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.EBU28531Front and rear brakes Brake levers and brake pedal
Check that there is no free play in the front brake
lever. If there is free play, have a Yamaha dealer
check the brake system.
Check for correct free play in the rear brake lever
and brake pedal. If the free play is incorrect, ad-
just it. (See page 8-42.)
Check operation of the levers and pedal. They
should move smoothly and there should be a
firm feeling when the brake is applied. If not,
have a Yamaha dealer check them.
Brake fluid level (front brake)
Check the brake fluid level. Add fluid if necessary.
(See page 8-40.)
Recommended brake fluid:
DOT 4
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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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6-2
6 Position (3):
Cold engine start with ambient temperature
above 25 °C (80 °F).
5. Apply the rear brake lever.
6. Completely close the throttle lever and start
the engine by pushing the start switch.
NOTICE: For maximum engine life, never
accelerate hard when the engine is cold!
[ECB00162]
TIP
If the engine fails to start, release the start
switch, then push it again. Pause a few seconds
before the next attempt. Each cranking should
be as short as possible to preserve battery ener-
gy. Do not crank the engine more than 10 sec-
onds on each attempt.
If the battery is discharged, pull the recoil starter
to start the engine.7. If the engine is started with the starter (choke)
in position (1), the starter (choke) should be
returned to position (2) to warm up the engine.
If the engine is started with the starter (choke)
in position (2), keep the starter (choke) in this
position to warm up the engine.
8. Continue warming up the engine until it idles
smoothly, then return the starter (choke) to
position (3) before riding.TIPThe engine is warm when it responds normally to
the throttle with the starter (choke) turned off.
1. Fully open
2. Half open
3. Closed
4. Starter (choke)U37S61E0.book Page 2 Tuesday, June 2, 2009 10:33 AM