2018 YAMAHA WOLVERINE engine

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8
EBU33661CoolantThe coolant level should be checked regular-
ly. In addition, the coolant must be changed
at the intervals specified in the periodic main-
tenance chart.TIPIf genuine Yamaha coolant is not available,
use an ethylene glycol antifreeze containing
corrosion inhibitors for aluminum engines and
mix with distilled water at a 1:1 ratio.
NOTICEECB02190Mix antifreeze with distilled water only.
However, 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 engine. To check the coolant level1. Park the vehicle on a level surface.
2. Wait for the engine to cool for an accurate reading.
3. Look the coolant level in the coolant res- ervoir.
Recommended coolant:YAMALUBE coolant
Coolant quantity: Coolant reservoir (up to full level):0.28 L (0.30 US qt, 0.25 Imp.qt)
Radiator (including all routes): 2.85 L (3.01 US qt, 2.51 Imp.qt)
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4. If the coolant is at or below the minimumlevel mark, remove the coolant reservoir
cap and add coolant to the maximum lev-
el mark.
5. Install the reservoir cap.
To change the coolant 1. Park the vehicle on a level surface.
2. Remove the hood. (See page 8-10.) 3. When the engine is cool, remove the radi-
ator cap. WARNING! Never attempt to
remove the radiator cap when the en-
gine is hot.
[EWB04250]
4. Place a container under the engine to col- lect the used coolant.
5. Remove the coolant drain bolt. Discard the used gasket.
1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
123
1. Radiator cap
1
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8
18. When coolant begins to flow out, tightenthe bleed bolt.
19. Start the engine and let it idle for ten mi- nutes.TIPWhile the engine is idling, check the cooling
system for leaks.
20. Rev the engine five times, then stop theengine and allow it to cool.TIPWhile waiting for the engine to cool, clean up
the used coolant and prepare it for disposal
according to local regulations. 21. When the engine is cool, remove the radi-
ator cap and check the coolant level in
the radiator. WARNING! Never attempt
to remove the radiator cap when the
engine is hot.
[EWB04250]
If necessary, add
coolant until the radiator is full. Install the
radiator cap.
22. Check the coolant level in the reservoir and replenish if necessary.
23. Install the panels and the hood.
EBU32400Axle bootsCheck the axle boots for holes or tears.
If any damage is found, have them replaced
by a Yamaha dealer.
1. Cylinder head air bleed boltTightening torque: Cylinder head air bleed bolt:10 N·m (1.0 kgf·m, 7.4 lb·ft)
1
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Inspection
The spark plug is an important engine com-
ponent and is easy to inspect. The condition
of the spark plug can indicate the condition of
the engine.
The ideal color of the porcelain insulator
around the center electrode is a medium-to-
light tan for a vehicle that is being ridden nor-
mally.
You should periodically remove and inspect
the spark plug because heat and deposits will
cause the spark plug to slowly break downand erode. If electrode erosion becomes ex-
cessive, or if carbon and other deposits are
excessive, you should replace the spark plug
with the specified plug.
Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.1. Spark plug wrench
1
Specified spark plug:
NGK/CPR7EA-91. Spark plug gap
1
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Installation1. Clean the surface of the spark plug gas-
ket and its mating surface, and then wipe
off any grime from the spark plug
threads.
2. Install the spark plug and tighten it to the specified torque. If a torque wrench is not
available when you are installing the
spark plug, a good estimate of the cor-
rect torque is one-quarter to one-half turn
past finger tight. Have the spark plug
tightened to the specified torque as soon
as possible.
3. Install the spark plug cap.
EBU33581Cleaning the air filter elementThe air filter element should be cleaned every
20–40 hours. It should be cleaned and lubri-
cated more often if the vehicle is operated in
extremely dusty areas. Each time air filter ele-
ment maintenance is performed, check the air
inlet to the air filter case for obstructions.
Check the air filter elem ent rubber joint to the
throttle body and manifold fittings for an air-
tight seal. Tighten all fittings securely to avoid
the possibility of unfiltered air entering the en-
gine.NOTICEECB02270Never operate the engine with the air filter
element removed. Doing so would allow
unfiltered air to enter, causing rapid en-
gine wear and possible engine damage.
Additionally, the fuel injection system
would be affected, re sulting in poor engine
performance and possible overheating.
Spark plug gap: 0.8–0.9 mm (0.031–0.035 in)
Tightening torque: Spark plug:11 N·m (1.1 kgf·m, 8.1 lb·ft)
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EBU33691V-belt case drain plugThe V-belt case drain plug is located behind
the left panel. (See page 8-11 for left panel re-
moval and installation procedures.)
After operating in water deep enough to allow
water to enter the V-belt case, remove the
drain plug to drain any water from the case.
If water drains from the V-belt case after re-
moving the drain plug, have a Yamaha dealer
inspect the vehicle, as the water may affect
other engine parts.
EBU32450Cleaning the spark arrester
WARNING
EWB03370Hot exhaust system may cause burns. To
avoid burns or fires, make sure that the en-
gine is stopped and the exhaust system is
cool before cleaning the spark arrester. Do
not start the engine while cleaning the ex-
haust system. 1. Remove the tailpipe bolts.
1. Air intake duct check hose
2. Air filter case check hose2
1
1. V-belt case drain plug
1
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EBU32460Valve clearanceThe correct valve clearance changes with
use, resulting in improper fuel/air supply or
engine noise. To prevent this, the valve clear-
ance must be adjusted regularly. This adjust-
ment however, should be left to a
professional Yamaha service technician.EBU32470BrakesReplacement of brake components requires
professional knowledge. Brake service
should be performed by a Yamaha dealer.
WARNING
EWB02572Operating with improperly serviced or ad-
justed brakes could lead to a loss in brak-
ing ability and an accident.
EBU32480Checking the front and rear brake padsEach brake pad is provided with wear indica-
tor grooves, which allow you to check the
brake pad wear without having to disassem-
ble the brake. To check the brake pad wear,
check the wear indicator grooves. If a brake
pad has worn to the point that the wear indi-
cator grooves have almost disappeared, have
a Yamaha dealer replace the brake pads as a
set.
The wheels need to be removed to check the
brake pads. (See pages 8-45, 8-47 for wheel
removal and installation procedures.)
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5. Start the engine. (See page 6-2.)
6. After the engine starts, disconnect thenegative lead of the jumper cable from
the frame and charged battery, and then
disconnect the positive lead of the jump-
er cable from the charged battery and the
battery in the vehicle.
7. Install the hood.
EBU32663Fuse replacementThe fuses are located under the hood. If an
electrical problem is suspected, check the
fuses and replace if necessary.
General layout
1. Jumper cable negative lead
1
1. Fuse box
2. Main fuse
3. EPS fuse
4. Fuel injection system fuse
5. Fuel injection system spare fuse
1 3
2
4
5
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