fuel YAMAHA WOLVERINE 400 2004 User Guide

5-11
CAUTION:_ Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system. _
WARNING
_

Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is over-
filled, fuel could spill out due to heat from
the engine or the sun.


Be careful not to spill fuel, especially on
the engine or exhaust pipe which can
cause a fire and severe injury. Wipe up any
spilled fuel immediately.


Do not refuel right after the engine has
been running and is still very hot.


Be sure the fuel tank cap is closed secure-
ly.
_
U5TE61.book Page 11 Tuesday, May 6, 2003 4:40 PM

6-3
EBU01265
Starting a cold engine
WARNING
_ Always 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. _1. Apply the rear brake lever.
2. Turn the fuel cock to “ON”.
3. Turn the main switch to “ON”, and then set
the engine stop switch to “”.
4. Shift the drive select lever into the neutral po-
sition.
U5TE61.book Page 3 Tuesday, May 6, 2003 4:40 PM

6-19
0–10 hours:
Avoid continuous operation above half throttle. Al-
low a cooling off period of five to ten minutes after
every hour of operation. Vary the speed of the ma-
chine from time to time. Do not operate it at one
set throttle position.
10–20 hours:
Avoid prolonged operation above 3/4 throttle. Rev
the machine freely but do not use full throttle at any
time.
After break-in:
Avoid prolonged full throttle operation. Vary
speeds occasionally.
EBU00211
Parking
When parking, stop the engine and shift into neu-
tral. Turn the fuel cock to “OFF” and apply the
parking brake.
U5TE61.book Page 19 Tuesday, May 6, 2003 4:40 PM

8-7
EBU00262
PERIODIC MAINTENANCE/LUBRICATION
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
Valves*Check valve clearance.
Adjust if necessary.
Cooling systemCheck coolant leakage.
Repair if necessary.
Replace coolant every 24 months.Spark plugCheck condition.
Adjust gap and clean.
Replace if necessary.Air filter elementClean.
Replace if necessary.Every 20–40 hours
(More often in wet or dusty areas.)
Carburetor*Check and adjust idle speed/starter operation.
Adjust if necessary.Crankcase breather
system*Check breather hose for cracks or damage.
Replace if necessary.Exhaust system*Check for leakage.
Retighten if necessary.
Replace gasket(s) if necessary.Fuel line*Check fuel hose for cracks or damage.
Replace if necessary.Engine oil
Replace. (Warm engine before draining.)Engine oil filter cartridge
Replace.Engine oil strainer*
Clean.Final gear oil
Check oil level/oil leakage.
Replace every 12 months.Differential gear oil
Front brake*Check operation/fluid leakage. (See NOTE page 8-8.)
Correct if necessary.Rear brakeCheck operation.
Adjust if necessary.U5TE61.book Page 7 Tuesday, May 6, 2003 4:40 PM

8-83
EBU00303
Valve clearance adjustment
The correct valve clearance changes with use, re-
sulting in improper fuel/air supply or engine noise.
To prevent this, the valve clearance must be ad-
justed regularly. This adjustment however, should
be left to a professional Yamaha service techni-
cian.
U5TE61.book Page 83 Tuesday, May 6, 2003 4:40 PM

8-129
EBU00413
Troubleshooting
Although Yamaha machines receive a rigid in-
spection before shipment from the factory, trouble
may occur during operation.
Any problem in the fuel, compression, or ignition
systems can cause poor starting and loss of pow-
er. The troubleshooting chart describes a quick,
easy procedure for making checks. If your ma-
chine requires any repair, take it to a Yamaha
dealer.
The skilled technicians at a Yamaha dealership
have the tools, experience, and know-how to prop-
erly service your machine. Use only genuine
Yamaha parts on your machine. Imitation parts
may look like Yamaha parts, but they are often in-
ferior. Consequently, they have a shorter service
life and can lead to expensive repair bills.
WARNING
Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe in-
jury or property damage. Make sure there are
no open flames or sparks in the area, including
pilot lights from water heaters or furnaces.
U5TE61.book Page 129 Tuesday, May 6, 2003 4:40 PM

8-131
EBU00724Troubleshooting chart
Starting problems or poor engine performance1. Fuel
Check if there is fuel
in the fuel tank.There is fuel.Turn the fuel cock
lever to “OFF”.No fuel.Fuel cock is
clogged.
Clean the
fuel cock. Some fuel.Turn the fuel cock
lever to “RES”.Restart the engine.
No fuel.Supply fuel.
2. Compression
Use the electric
starter to see if
there is compression.There is compression.
Compression normal.
No compression.Ask a Yamaha dealer to
inspect.
3. Ignition
Remove the
spark plug and
check electrodes.WetWipe clean with dry cloth.
DryAttach spark plug cap and
ground to chassis.Use the
electric starter.Spark is good.Ignition system is
normal.
Spark is weak.
Adjust the spark plug gap
or replace the spark plug. No spark.
Ask a Yamaha dealer to
inspect. 4. Battery
Use the electric starter.Engine turns over
quickly.Battery is good.
Engine turns over
slowly.Check the connections.Check the
fuel flow.
Turn the fuel cock
lever to “ON”.
Remove the fuel hose
from the fuel cock.
U5TE61.book Page 131 Tuesday, May 6, 2003 4:40 PM

9-7
EBU00427
B. STORAGE
Long term storage (60 days or more) of your ma-
chine will require some preventive procedures to
guard against deterioration. After thoroughly
cleaning the machine, prepare for storage as fol-
lows:
1. Fill the fuel tank with fresh fuel and add fuel
stabilizer (if available).NOTE:Use of fuel stabilizer eliminates the need to drain
the fuel system. Consult a Yamaha dealer if the
fuel system is to be drained instead.2. Remove the spark plug, pour about one ta-
blespoon of SAE 10W30 or 20W40 motor oil
in the spark plug hole and reinstall the spark
plug. Ground the spark plug wire and turn the
engine over several times to coat the cylinder
wall with oil.
3. Lubricate all control cables.
4. Block up the frame to raise all wheels off the
ground.
U5TE61.book Page 7 Tuesday, May 6, 2003 4:40 PM

10-1
EBU00428
SPECIFICATIONS
Model YFM400FA
Dimensions:
Overall length 1,984 mm
Overall width 1,085 mm
Overall height 1,120 mm
Seat height 827 mm
Wheelbase 1,233 mm
Ground clearance 245 mm
Minimum turning radius 3,000 mm
Basic weight:
With oil and full fuel tank 265 kg
Noise and vibration level:
Noise level (77/311/EEC) (for Europe) 77.2 dB(A)
Vibration on seat (EN1032, ISO5008) (for Europe) Will not exceed 0.6 m/s
2
Vibration on handlebar (EN1032, ISO5008)
(for Europe)Will not exceed 2.5 m/s
2
Engine:
Engine type Liquid-cooled 4-stroke, SOHC
Cylinder arrangement Forward-inclined single cylinder
Displacement 401 cm
3
Bore
× stroke 84.5
× 71.5 mm
Compression ratio 10.5 :1
Starting system Electric and recoil starter
Lubrication system Wet sump
U5TE61.book Page 1 Tuesday, May 6, 2003 4:40 PM

10-3
Final gear oil:
Type SAE 80 API GL-4 Hypoid gear oil
Quantity 0.23 L
Differential gear oil:
Type SAE 80 API GL-4 Hypoid gear oil
Quantity 0.35 L
Radiator capacity (including all routes): 1.32 L
Air filter: Wet element
Fuel:
Type Unleaded gasoline only
For Europe: Regular unleaded gasoline only with a
research octane number of 91 or higher
Fuel tank capacity 15 L
Fuel reserve amount 4.5 L
Carburetor:
Type/quantity BSR33/1
Manufacturer MIKUNI
Spark plug:
Type/manufacturer DR8EA / NGK
Spark plug gap 0.6–0.7 mm
Clutch type: Wet, centrifugal automaticModel YFM400FA
U5TE61.book Page 3 Tuesday, May 6, 2003 4:40 PM