2008 YAMAHA WOLVERINE 350 check engine

6-1
6
EBU19880
OPERATION
EBU19900Read the Owner’s Manual carefully before riding
the ATV.
WARNING
EWB00630Read 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. If there is a control or func-
tion you do not understand, ask your Yamahadealer.EBU26950Starting a cold engine
WARNING
EWB00640Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or do
not work smoothly, you could be unable to
control the ATV, which could lead to an acci-dent or collision.
CAUTION:ECB00150See the “Engine break-in” section on page 6-4prior to operating the engine for the first time.
1. Set the parking brake.
2. Turn the fuel cock to “ON”.
3. Turn the main switch to “ON” and the engine
stop switch to “”.
4. Shift the drive select lever into the neutral po-
sition. The neutral indicator light should come
on. If the indicator light does not come on,
have a Yamaha dealer check the electrical cir-
cuit.NOTE:The engine can be started under the following con-
ditions:
The drive select lever is in the neutral position.
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 position beforestarting the engine.
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6-4
63. Shift from neutral to reverse and vice versa by
moving the drive select lever along the shift
guide.
NOTE:When in reverse, the reverse indicator light should
come on. If the indicator light does not come on,have a Yamaha dealer check the electrical circuit.
4. 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.
WARNING
EWB00720Improper operation in reverse could make you
hit an obstacle or even a person behind you,
resulting in serious injury. When you shift into
reverse, make sure there are no people or ob-
stacles behind you. When it is safe to proceed,go slowly.EBU20682Engine break-in NOTE:
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 orhour 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
1. Drive select lever
2. F (Forward)
3. N (Neutral)
4. R (Reverse)U3D562E0.book Page 4 Wednesday, June 6, 2007 12:58 PM

6-5
6 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.
CAUTION:ECB00220If any engine trouble should occur during the
engine break-in period, immediately have aYamaha dealer check the ATV.
EBU20700Parking When parking the ATV, stop the engine, shift the
drive select lever into the forward position, apply
the parking brake, and then turn the fuel cock to
“OFF”.EBU20760Parking on a slope
WARNING
EWB00830Avoid parking on hills or other inclines. Park-
ing on a hill or other incline could cause the
ATV to roll out of control, increasing the
chance of an accident. If you must park on an
incline, place the ATV transversely across the
incline, shift the drive select lever to the for-
ward position, stop the engine, apply the park-
ing brake, and then block the front and rear
wheels with rocks or other objects.
Do not park the ATV at all on hills that are sosteep you could not walk up them easily.
1. Bring the ATV to a stop by applying the brakes
in the forward position.
2. Stop the engine.
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8-3
8
EBU21742Periodic maintenance chart for the emission control system NOTE:
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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8-6
8
9*V- b e l tCheck for wear, cracks or other damage, and re-
place if necessary.√ √√√
10*Chassis fastenersMake sure that all nuts, bolts, and screws are
properly tightened.√√√√√
11*Shock absorber as-
sembliesCheck operation and correct if necessary.
Check for oil leakage and replace if necessary.√√√
12*Steering shaftLubricate with lithium-soap-based grease.√√√
13*Steering systemCheck operation and repair or replace if damaged.
Check toe-in and adjust if necessary.√√√√√
14*Engine mountCheck for cracks or other damage, and replace if
necessary.√√√
15*Axle bootsCheck for cracks or other damage, and replace if
necessary.√√√√√
16 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√
17Engine oil filter car-
tridgeReplace.√√√
18*Engine oil strainerClean.√√√
19 Final gear oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√√
20*Moving parts and
cablesLubricate.√√√√ 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
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8-8
8
EBU23080Removing and installing the panel The panel shown needs to be removed to perform
some of the maintenance jobs described in this
chapter. Refer to this section each time the panel
needs to be removed and installed.EBU23111Panel A
To remove the panelRemove the bolt, and then take the panel off.To install the panel
Place the panel in the original position and install
the bolt.CAUTION:ECB00380When installing the panel, be sure not to pinchthe cables or wires.EBU23211Checking 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
1. Panel A
1. Panel A
2. Bolt
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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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8-10
8 To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.
2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
NOTE:If a torque wrench is not available when installing
a spark plug, a good estimate of the correct torque
is 1/4–1/2 turn past finger tight. However, the spark
plug should be tightened to the specified torque assoon as possible.
4. Install the spark plug cap.EBU23313Engine oil and oil filter cartridge The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter cartridge replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Place the ATV on a level surface. Specified spark plug:
NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1. Spark plug gap
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)
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