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9-12
94. Install the fuel tank cap.
To install the panel
1. Remove the fuel tank cap.
2. Place the panel over the fuel tank filler tube, and then install the fuel tank cap.
3. Install the bolts and quick fasteners.
4. Install the seat.
Panels B and C
When removing or installing panel C, the drive se-
lect lever must be moved out of the park position.
Apply the brake pedal and move the drive select
lever to the reverse position. To remove a panel
1. Remove panel A.
2. Pull the panel upward to release the tabs as
shown.
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9-36
912. Install the air filter case cover by hooking the
holders onto the cover. NOTICE: Make sure
that the air filter element is properly seated
in the air filter case. Never operate the en-
gine with the air filter element removed.
Doing so would allow unfiltered air to enter
the engine, causing rapid engine wear and
possible engine damage. Additionally, the
fuel injection system would be affected re-
sulting in poor engine performance and
possible overheating.
[ECB00763]
13. Install the seat.EBU28905Cleaning the spark arresterBe sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
WARNING
EWB02342Always let the exhaust system cool prior to
touching exhaust components.
Do not start the engine with the spark arrester
removed. Sparks or exhaust particulate can
cause eye injury, burns, or start a fire. 1. Remove the tailpipe bolts.
2. Remove the tailpipe by pulling it out of the muffler, and then remove the gasket.1. Gasket
2. Spark arrester
3. Tailpipe
4. Tailpipe bolt
3
2
4
1
4
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9-39
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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9-57
9
EBU30806Replacing a fuse
If an electrical problem is suspected, check the
fuse and replace it if necessary as follows.NOTICEECB00641To prevent accidental short-circuiting, turn off
the main switch when checking or replacing a
fuse. 1. Turn off all electrical systems. (See page 5-1.)
1. Fuel injection system spare fuse
2. Fuel injection system fuse
3. Main fuse
4. EPS fuse (equipped models)
5. Fuse box
1
2
3
4
5
1. Auxiliary DC jack fuse
2. Four-wheel-drive motor fuse
3. Ignition fuse
4. Radiator fan motor fuse
5. Signaling system fuse
6. Headlight fuse
7. Spare fuse
1
2
34
5
6
7
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9-58
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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9-65
9
2. Lower the ATV to the ground.
3. Tighten the wheel nuts to the specified
torques.
EBU25741TroubleshootingAlthough Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the
fuel, compression, or ignition systems, for exam-
ple, can cause poor starting and loss of power.
The following troubleshooting charts represent
quick and easy procedures for checking these vi-
tal systems yourself. However, should your ATV
require any repair, take it to a Yamaha dealer,
whose skilled technicians have the necessary
tools, experience, and know-how to service the
ATV properly.
Use only genuine Yamaha replacement parts. Im-
itation parts may look like Yamaha parts, but they
are often inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWB02281Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe inju-
ry or property damage. Make sure there are no
open flames or sparks in the area, including pi-
lot lights from water heaters or furnaces.
1. Tapered nutTightening torques:Front wheel nut:55 N·m (5.5 kgf·m, 41 lb·ft)
Rear wheel nut: 55 N·m (5.5 kgf·m, 41 lb·ft)1
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9
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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10
EBU27264StorageShort-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover. NOTICE: Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.
[ECB00722]
Long-term
Before storing your ATV for several months: 1. Make any necessary repairs and perform all outstanding maintenance.
2. Follow all the instructions in the Cleaning sec- tion of this chapter.
3. Fill up the fuel tank and add fuel stabilizer (Fu- el Med Rx if available), and then run the en-
gine for 5 minutes to distribute the treated
fuel. 4. Perform the following steps to protect the en-
gine from internal corrosion.a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place the spark plug on the
cylinder head so that the electrodes are
grounded. (This will limit sparking during
the next step.)
d. Turn the engine over several times with the starter. (This will coat the cylinder wall
with oil.)
e. Remove the spark plug cap from the spark plug, and then install the spark plug and
the spark plug cap.
5. Lubricate all control cables and the pivoting points of all levers and pedals.
6. Put the frame on stands or blocks to raise all wheels off the ground. (Alternatively, turn the
wheels each month to prevent the tires from
degrading in one spot.)
7. Cover the muffler outlet with a plastic bag to prevent moisture from entering it.
Specified amount:
7.5 ml per liter of fuel (1 oz per gallon)UBEY60E0.book Page 2 Monday, July 27, 2020 10:46 AM