2002 YAMAHA KODIAK 400 engine

8-73 1. Air filter element
1.Élément de filtre à air
1. Elemento del filtro de aire
1. Air filter guide
1. Guide de filtre à air
1. Filtro de aire guía
3. Remove the air filter element, and separate it
from the guide.
4. Wash the element gently but thoroughly in
solvent.
WARNING
Always use parts cleaning solvent to clean the
air filter element. Never use low flash point sol-
vents or gasoline to clean the air filter element
because the engine could catch fire or ex-
plode.5. Squeeze the excess solvent out of the filter
and let it dry.CAUTION:
Do not twist the filter element when squeezing
it.6. Inspect the element. If damaged, replace it.
7. Apply SAE 10W30 motor oil to the element.NOTE:The element should be wet but not dripping.
U5GH62.book Page 73 Monday, August 6, 2001 9:09 AM

8-75 1. Connect the hose.
1. Brancher le flexible.
1. Conecte la manguera.
8. Reinstall the element to the element guide.
9. Reinstall the element assembly and parts re-
moved for access.NOTE:The air filter element should be cleaned every 20 ~
40 hours. It should be cleaned and lubricated more
often if the machine is operated in extremely dusty
areas. Each time filter element maintenance is
performed, check the air inlet to the filter case for
obstructions. Check the air cleaner rubber joint to
the carburetor and manifold fittings for an air-tight
seal. Tighten all fittings securely to avoid the pos-
sibility of unfiltered air entering the engine.CAUTION:
Never operate the engine with the air filter ele-
ment removed. This will allow unfiltered air to
enter, causing rapid engine wear and possible
engine damage. Additionally, operation with-
out the filter element will affect carburetor jet-
ting with subsequent poor performance and
possible engine overheating.
U5GH62.book Page 75 Monday, August 6, 2001 9:09 AM

8-81
EBU00296
Carburetor adjustment
The carburetor is a vital part of the engine and re-
quires very sophisticated adjustment. Most adjust-
ing should be left to a Yamaha dealer who has the
professional knowledge and experience to do so.
However, the idling speed may be performed by
the owner as a part of the usual maintenance rou-
tine.CAUTION:
The carburetor was set at the Yamaha factory
after many tests. If the settings are disturbed
by someone without sufficient technical
knowledge, poor engine performance and
damage may result.
U5GH62.book Page 81 Monday, August 6, 2001 9:09 AM

8-83 1. Throttle stop screw
1. Vis d’arrêt de l’accélérateur
1. Tornillo de tope del acelerador
EBU00657
Idle speed adjustmentNOTE:A diagnostic tachometer must be used for this pro-
cedure.1. Start the engine and warm it up for a few min-
utes at approximately 1,000 to 2,000 r/min.
Occasionally rev the engine to 4,000 to
5,000 r/min. The engine is warm when it
quickly responds to the throttle.
2. Remove panel D. (See pages 8-17 ~ 8-21 for
removal and installation procedures.)
3. Connect the tachometer and set the idle to
the specified idling speed by adjusting the
throttle stop screw. Turn the screw in to in-
crease engine speed, and out to decrease
engine speed.
4. Install the panel.Specified idle speed:
1,450 ~ 1,550 r/min
U5GH62.book Page 83 Monday, August 6, 2001 9:09 AM

8-85
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.
U5GH62.book Page 85 Monday, August 6, 2001 9:09 AM

8-87 1. Locknut 2. Adjusting bolt
1. Contre-écrou 2. Bolhon de réglage
1. Contratuerca 2. Perno de ajuste
a. Free play
a. Jeu
a. Juego libre
EBU00307
Throttle lever adjustmentNOTE:Adjust the engine idling speed before adjusting the
throttle lever free play.1. Loosen the locknut.
2. Turn the adjusting bolt until the throttle lever
free play is 3 ~ 5 mm.
3. Tighten the locknut.
U5GH62.book Page 87 Monday, August 6, 2001 9:09 AM

8-105
EBU00570
Cable inspection and lubrication
WARNING
Inspect cables frequently and replace if dam-
aged. Corrosion can result when the outer cov-
ering of control cables becomes damaged.
Cables can also become frayed or kinked. Op-
eration of controls could be restricted, which
could cause an accident or injury.Lubricate the inner cables and the cable ends. If
the cables do not operate smoothly, ask a Yamaha
dealer to replace them.
Recommended lubricant:
Engine oil
U5GH62.book Page 105 Monday, August 6, 2001 9:09 AM

8-135
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.
U5GH62.book Page 135 Monday, August 6, 2001 9:09 AM