2008 YAMAHA WOLVERINE 350 light

8-9
8plug 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 the spark plug cap.
2. 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).
NOTE:If 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.
2. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
1. Spark plug cap
1. Spark plug wrench
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83. 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. Insert the tailpipe into the muffler and align the
bolt holes.
5. Install the tailpipe cover by installing the bolts,
and then tighten them to the specified torque.
WARNING
EWB02340Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior totouching exhaust components.EBU23920V-belt cooling duct check hose If dust or water collects in the V-belt cooling duct
check hose, remove the hose and clean it.
1. Tailpipe
2. Spark arresterTightening torque:
Tailpipe bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1. V-belt cooling duct check hose (left front side of ATV)
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8-31
8
WARNING
EWB02080Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.
After servicing:
Make sure the brakes operate smoothly and
that the free play is correct.
Make sure the brakes do not drag.
Replacement of brake components requires
professional knowledge. These proceduresshould be performed by a Yamaha dealer.
EBU24230Axle boots The axle boots must be checked for damage at the
intervals specified in the periodic maintenance and
lubrication chart. Check the axle boots for tears or
damage. If any damage is found, have them re-
placed by a Yamaha dealer.EBU24751Brake light switches The operation of the brake light switches must be
checked and, if necessary, adjusted at the inter-
vals specified in the periodic maintenance and lu-
brication chart.
The brake light switch for the brake pedal can be
adjusted as follows, but the other brake light
switches should be adjusted by a Yamaha dealer.
1. Remove panel A. (See page 8-8.)NOTE:The brake light switch is properly adjusted when
the brake light comes on just before braking takeseffect.
1. Distance between brake pedal and footboard bracket
1 1
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8-32
8 2. Turn the adjusting nut while holding the brake
light switch in place. To make the brake light
come on earlier, turn the adjusting nut in direc-
tion (a). To make the brake light come on lat-
er, turn the adjusting nut in direction (b).
3. Install the panel.
EBU24900Checking and lubricating the cables The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02130Inspect cables frequently and replace if dam-
aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could re-
strict the operation of controls and lead to anaccident or injury.EBU28710Checking and lubricating the front and
rear brake levers The operation of the front and rear brake levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
1. Brake light switch
2. Brake light switch adjusting nut
Recommended lubricant:
Engine oil
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8-36
8
EBU25324Replacing a fuse
The main fuse and the fuse box are located under
the seat. (See page 4-11.)
If a fuse is blown, replace it as follows.
1. Turn the key to “OFF” and turn off all electrical
circuits.CAUTION:ECB00640To prevent accidental short-circuiting, turn off
the main switch when checking or replacing afuse.
1. Main fuse
2. Spare main fuse
3. Fuse box
1. Headlight fuse
2. Ignition fuse
3. Signaling system fuse
4. Spare fuse
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8-37
82. Remove the blown fuse, and then install a
new fuse of the specified amperage.
WARNING
EWB02171Always use a fuse of the specified rating, and
never use a substitute object in place of the
proper fuse. An improper fuse or a substitute
object can cause damage to the electrical sys-tem, which could lead to a fire.
3. Turn the key to “ON” and turn on the electrical
circuits to check if the devices operate.
4. If the fuse immediately blows again, have a
Yamaha dealer check the electrical system.
EBU25541Replacing a headlight bulb If a headlight bulb burns out, replace it as follows.
1. Remove the headlight bulb holder cover at the
rear of the headlight by pulling it off.
2. Remove the headlight bulb holder by pushing
it inward and turning it counterclockwise. Specified fuses:
Main fuse:
20.0 A
Headlight fuse:
15.0 A
Ignition fuse:
15.0 A
Signaling system fuse:
10.0 A1. Headlight bulb holder cover
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8 3. Remove the defective bulb from the headlight
unit by pulling it out.
WARNING
EWB02220A headlight bulb is hot when it is on and imme-
diately after it is turned off. Wait for the bulb to
cool before touching or removing it. You can
be burned or a fire could start if the bulb touch-es something flammable.
4. Install a new headlight bulb into the headlight
unit by aligning the projection on the bulb with
the groove in the headlight unit.
CAUTION:ECB00650Do not touch the glass part of the headlight
bulb to keep it free from oil, otherwise the
transparency of the glass, the luminosity of the
bulb, and the bulb life will be adversely affect-
ed. Thoroughly clean off any dirt and finger-
prints on the headlight bulb using a clothmoistened with alcohol or thinner.
5. Install the headlight bulb holder by aligning the
projections with the holes in the headlight unit,
pushing it inward, and turning it clockwise until
it stops.
1. Headlight bulb holder
1. Do not touch the glass part of the bulb.
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86. Install the headlight bulb holder cover at the
rear of the headlight.
CAUTION:ECB00670Make sure the headlight bulb holder cover is
securely fitted over the bulb holder and seatedproperly.
7. Adjust the headlight beam if necessary.EBU25560Adjusting a headlight beam CAUTION:ECB00690It is advisable to have a Yamaha dealer makethis adjustment.To raise a headlight beam, turn the adjusting bolt
in direction (a).
To lower a headlight beam, turn the adjusting bolt
in direction (b).
EBU25600Replacing the tail/brake light bulb If the tail/brake light bulb burns out, replace it as
follows.
1. Remove the lens by removing the screws.1. Headlight beam adjusting bolt
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