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9
EBU23473CoolantThe coolant level should be checked regularly. In
addition, the coolant must be changed at the in-
tervals specified in the periodic maintenance
chart.TIPIf genuine Yamaha coolant is not available, use an
ethylene glycol antifreeze containing corrosion in-
hibitors for aluminum engines and mix with dis-
tilled water at a 1:1 ratio.
NOTICEECB02190Mix antifreeze with distilled water only. Howev-
er, if distilled water is not available, soft water
may be used for refilling. Do not use hard water
or salt water since they are harmful to the en-
gine. EBU2712ATo check the coolant level1. Park the ATV on a level surface.TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture. 2. Check the coolant level in the coolant reser- voir.TIPThe coolant should be between the minimum and
maximum level marks.
Recommended coolant:YAMALUBE coolant
Coolant quantity: Coolant reservoir (up to full level):0.25 L (0.26 US qt, 0.22 Imp.qt)
Radiator (including all routes): 1.32 L (1.40 US qt, 1.16 Imp.qt)
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9-30
93. If the coolant is at or below the minimum level
mark, remove panel C to access the coolant
reservoir. (See page 9-10.)
4. Remove the coolant reservoir cap. WARNING! Remove only the coolant res-
ervoir cap. Never attempt to remove the
radiator cap when the engine is hot.
[EWB02672]
5. Add coolant to the maximum level mark, in-stall the reservoir cap, and then install the
panel. NOTICE: If coolant is not available,
use distilled water or soft tap water in-
stead. Do not use hard water or salt water
since they are harmful to the engine. If wa-
ter has been used instead of coolant, re-
place it with coolant as soon as possible,
otherwise the cooling system will not be
protected against frost and corrosion. If
water has been added to the coolant, have
a Yamaha dealer check the antifreeze con-
1. Maximum level mark
2. Minimum level mark
1
2
1. Coolant reservoir cap
1
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9
12. Pour the recommended coolant into the radi-
ator until it is full, and then install the radiator
cap.
13. Start the engine, let it idle for several minutes, and then turn it off.
TIPWhile the engine is idling, check the cooling sys-
tem for leaks. 14. When the engine is cool, remove the radiatorcap to check the coolant level in the radiator.
If it is low, add sufficient coolant until it reach-
es the top of the radiator, and then install the
radiator cap.
15. Install the panels and the front carrier.EBU37113Cleaning the air filterThe main air filter element and sub air filter ele-
ment should be cleaned every 20–40 hours of en-
gine operation. When servicing the air filter
elements, check the air filter case inlet for obstruc-
tions. Check the air filter case rubber joint to the
throttle body and the rubber joint manifold fittings
for an air-tight seal. Tighten all fittings securely to
avoid the possibility of unfiltered air entering the
engine.
TIP Replace the air filter elements if damaged.
Service the air filter more frequently if you often
ride in wet or dusty areas.
There is a check hose at the bottom of the air fil-
ter case. If dust or water collects in this hose,
empty the hose and clean the air filter case and
air filter elements. 1. Park the ATV on a level surface.
2. Remove the seat. (See page 5-18.)
3. Remove the air filter case cover by unhooking
the air filter case cover holders.1. Air filter case check hose
1
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9
5. Pull off the lock plate from the main air filter
assembly, and then remove the air filter ele-
ment (sponge material) from the frame.
6. Wash the air filter elements gently but thor- oughly with YAMALUBE Air Filter Cleaner, or
a dedicated parts cleaning solvent.
WARNING! Always use parts cleaning sol- vent. Never use low-flash-point solvents
or gasoline because the engine could
catch fire or explode.
[EWB01943]
7. Squeeze out the excess moisture, and let dry. NOTICE: Do not twist the sponge material
when squeezing it.
[ECB00442]
8. Check the air filter elements (sponge material) for damage, replace if necessary.
9. Apply YAMALUBE Foam Air Filter Oil (or equivalent) to the air filter elements.TIPThe sponge material should be wet but not drip-
ping. 10. Install the sub air filter element.
11. Install the main air filter element onto its frame, then the lock plate, and then install the
main air filter assembly.
1. Frame
2. Air filter element (sponge material)
3. Lock plate
1
2
3
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9
3. Tap the tailpipe lightly, and then use a wire
brush to remove any carbon deposits from
the spark arrester portion of the tailpipe and
inside of the tailpipe housing.
4. Check the gasket for damage. Replace if nec- essary.
5. Install the gasket onto the tailpipe, then insert the tailpipe into the muffler and align the bolt
holes.
6. Install the bolts and tighten to the specified torque.
EBU23921V-belt cooling duct check hoseIf dust or water collects in the V-belt cooling duct
check hose, remove the hose and clean it.
EBU23932V-belt case drain plugAfter riding in water deep enough to allow it to en-
ter the V-belt case, remove the V-belt case drain
plug to drain the water from the case.TIPIf water drains from the V-belt case after removing
the plug, have a Yamaha dealer check the ATV as
the water may affect other engine parts.
Tightening torque:Tailpipe bolt:10 N
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9
For differential gear lock models
Periodically check the throttle lever free play and
adjust if necessary.
1. Slide the rubber cover back.
2. Loosen the locknut. 3. To increase the throttle lever free play, turn
the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24062Valve clearanceThe valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance chart.EBU29602BrakesReplacement of brake components requires pro-
fessional knowledge. Brake service should be
performed by a Yamaha dealer.
WARNING
EWB02572Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.
1. Throttle lever free play
2. Rubber cover
3. Locknut
4. Throttle lever free play adjusting boltThrottle lever free play: 2.0–4.0 mm (0.08–0.16 in)
2WD
4WD
3
4
2
1
(b)
(a)
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92. Remove the seat. (See page 5-18.)
3. Remove the blown fuse, and then install a
new fuse of the specified amperage.
WARNING! Always use a fuse of the spec-
ified rating, and never use a substitute ob-
ject in place of the proper fuse. An
improper fuse or a substitute object can
cause damage to the electrical system,
which could lead to a fire.
[EWB02173]
4. Turn on the main switch, start the engine, andthen turn on the circuit in question.
5. If the fuse immediately blows again, have a Yamaha dealer check the vehicle.
Specified fuses:
Main fuse:40.0 A
Headlight fuse: 15.0 A
Ignition fuse: 10.0 A
Four-wheel-drive motor fuse: 10.0 A (YFM450FWBD)
3.0 A (YFM450FWB)
Signaling system fuse: 10.0 A
Radiator fan motor fuse: 20.0 A
Auxiliary DC jack fuse: 10.0 A
Fuel injection system fuse: 10.0 A
EPS fuse: 40.0 A (YFM450FWBD)
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EBU27696Troubleshooting chartsStarting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
Operate the electric starter.4. Compression
There is compression.
There is no compression.
The engine does not start.
Have a Yamaha dealer check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug. Have a Yamaha dealer check the ATV.
The engine does not start.
Check the compression.
DryWet
Operate the electric starter.
Have a Yamaha dealer check the ATV.
The engine does not start.
Check the ignition.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
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