2003 YAMAHA WARRIOR 350 service

8-8 * It is recommended that these items be serviced by a Yamaha dealer.
** Lithium-soap-based grease
NOTE:

Recommended brake fluid: DOT 4


Brake fluid replacement:
1. When disassembling the master cylinder or caliper cylinder, replace the brake fluid. Normally check
the brake fluid level and add fluid as required.
2. On the inner parts of the master cylinder and caliper cylinder, replace the oil seals every two years.
3. Replace the brake hoses every four years, or if cracked or damaged.
Wheel bearings*•Check bearing assembly for looseness/damage.
•Replace if damaged.Steering system*•Check operation.
•Repair if damaged.
•Check toe-in.
•Adjust if necessary.Upper and lower arm
pivot and steering
shaft*•Lubricate every 6 months.**Rear arm pivot*•Lubricate every 6 months.**Fittings and Fasteners*•Check all chassis fittings and fasteners.
•Correct if necessary.Battery*•Check specific gravity.
•Check breather hose for proper routing.
•Correct if necessary.
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
U5NF61.book Page 8 Wednesday, June 13, 2001 5:18 PM

8-37 1. Locknut 2. Adjusting bolt a. 3 ~ 5 mm
1. Contre-écrou 2. Boulon de réglage
1. Contratuerca 2. Perno de ajuste
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.
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.
U5NF61.book Page 37 Wednesday, June 13, 2001 5:18 PM

8-45
EBU00820*
Brake fluid replacement
1. Complete fluid replacement should be done
only by trained Yamaha service personnel.
2. Have a Yamaha dealer replace the following
components during periodic maintenance or
when they are damaged or leaking.

Replace all rubber seals every two years.


Replace all hoses every four years.
U5NF61.book Page 45 Wednesday, June 13, 2001 5:18 PM

8-47 a. Zero mm
a.Zéro mm
a. Cero mm
EBU00951
Front brake adjustment
The front brake lever should have a free play of
zero mm at the lever end. If not, ask a Yamaha
dealer to adjust it.
WARNING
_ Operating 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.


Make sure the brakes are not spongy. All
air must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These procedures
should be performed by a Yamaha dealer.
U5NF61.book Page 47 Wednesday, June 13, 2001 5:18 PM

8-49 a. 10 mm
EBU00952*
Rear brake adjustment
Pedal height adjustment
The top of the brake pedal should be positioned
10 mm below the top of the footboard. If not, ask a
Yamaha dealer to adjust it.
WARNING
_ Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident. After servic-
ing:

Make sure the brakes operate smoothly
and that the brake pedal position is cor-
rect.


Make sure the brakes do not drag.


Make sure the brakes are not spongy. All
air must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These procedures
should be performed by a Yamaha dealer.
_
U5NF61.book Page 49 Wednesday, June 13, 2001 5:18 PM

8-63 1. O-rings
1. Joints toriques
1. Juntas tóricas
EBU00805
Lubricating the drive chain
The drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
and lubrication chart, otherwise it will quickly wear
out, especially when riding in dusty or wet areas.
Service the drive chain as follows.CAUTION:_ The drive chain must be lubricated after wash-
ing the ATV or riding in the rain. _1. Clean the drive chain with kerosene and a
small soft brush.CAUTION:_ To prevent damaging the O-rings, do not clean
the drive chain with steam cleaners, high-pres-
sure washers or inappropriate solvents. _2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a
special O-ring chain lubricant.CAUTION:_ Do not use engine oil or any other lubricants
for the drive chain, as they may contain sub-
stances that could damage the O-rings. _
U5NF61.book Page 63 Wednesday, June 13, 2001 5:18 PM

8-97
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.
U5NF61.book Page 97 Wednesday, June 13, 2001 5:18 PM

10-2
10
Engine oil:
Type
Recommended engine oil classification: API Service SE, SF, SG type or higherMODEL YFM350X
-20˚-10˚0˚
10˚20˚30˚40˚50˚C
10W/30
15W/4020W/4020W/50
10W/40
5W/30
CAUTION:
Be sure to use motor oils that do not contain anti-
friction modifiers. Passenger car motor oils (often
labeled “ENERGY CONSERVING II”) contain anti-
friction additives which will cause clutch and/or
starter clutch slippage, resulting in reduced com-
ponent life and poor engine performance.
U5NF61.book Page 2 Wednesday, June 13, 2001 5:18 PM