ATV Arctic Cat 2002. Service Manual - part 25

11-2

Engine

!

NOTE: A Condition/Remedy marked with an

asterisk (*) is for manual transmission models
only.

Problem: Engine will not start or is hard to start (Compression too low)

Condition

Remedy

1.

Valve clearance

 out of adjustment

2.

Valve guides

 worn - seated poorly

3.

Valves

 mistimed

4.

Piston rings

 worn excessively

5.

Cylinder bore

 worn

6.

Spark plug

 seating poorly

7.

Starter motor

 cranks too slowly - does not turn

1. Adjust clearance

2. Repair - replace guides

3. Adjust valve timing

4. Replace rings

5. Replace - rebore cylinder

6. Tighten plug

7. See Electrical in this section

Problem: Engine will not start or is hard to start (No spark)

Condition

Remedy

1.

Spark plug

 fouled

2.

Spark plug

 wet

3.

Magneto

 defective

4.

CDI unit

 defective

5.

Ignition coil

 defective

6.

High-tension lead

 open - shorted

1. Clean - replace plug

2. Clean - dry plug

3. Replace magneto

4. Replace CDI unit

5. Replace ignition coil

6. Replace high tension lead

Problem: Engine will not start or is hard to start (No fuel reaching the carburetor)

Condition

Remedy

1.

Gas tank vent hose

 obstructed

2.

Carburetor inlet needle

 defective

3.

Fuel hose

 obstructed

4.

Fuel screens

 obstructed

1. Clean vent hose

2. Replace needle

3. Clean - replace hose

4. Clean - replace inlet screen - valve screen

Problem: Engine stalls easily

Condition

Remedy

1.

Spark plug

 fouled

2.

Magneto

 defective

3.

CDI unit

 defective

4.

Carburetor jets

 obstructed

5.

Valve clearance

 out of adjustment

1. Clean plug

2. Replace magneto

3. Replace CDI unit

4. Clean jets

5. Adjust clearance

Problem: Engine noisy (Excessive valve chatter)

Condition

Remedy

1.

Valve clearance

 too large

2.

Valve spring(s)

 weak - broken

3.

Rocker arm

 - 

rocker arm shaft

 worn

4.

Camshaft

 worn

1. Adjust clearance

2. Replace spring(s)

3. Replace arm - shaft

4. Replace camshaft

RepairPro Service Manual

11-3

11

Problem: Engine noisy (Noise seems to come from piston)

Condition

Remedy

1.

Piston - cylinder

 worn

2.

Combustion chamber carbon

 buildup

3.

Piston pin - piston pin bore

 worn

4.

Piston rings - ring groove(s)

 worn

1. Replace - service piston - cylinder

2. Clean chamber

3. Replace - service pin - bore

4. Replace rings - piston

Problem: Engine noisy (Noise seems to come from timing chain)

Condition

Remedy

1.

Chain

 stretched

2.

Sprockets

 worn

3.

Tension adjuster

 malfunctioning

1. Replace chain

2. Replace sprockets

3. Repair - replace adjuster

Problem: Engine noisy (Noise seems to come from clutch)

Condition *

Remedy *

1.

Crankshaft splines - bearings

 worn

2.

Countershaft - hub splines

 worn

3.

Clutch plate teeth

 worn

4.

Driven - drive clutch plates

 distorted - broken

5.

Clutch dampers 

weak

1. Replace crankshaft - bearings

2. Replace countershaft - hub

3. Replace clutch plate(s)

4. Replace clutch plate(s)

5. Replace dampers

Problem: Engine noisy (Noise seems to come from crankshaft)

Condition

Remedy

1.

Bearing

 worn - burned

2.

Lower rod-end bearing

 worn - burned

3.

Connecting rod side clearance

 too large

1. Replace bearing

2. Replace bearing

3. Replace thrust washer(s)

Problem: Engine noisy (Noise seems to come from transmission)

Condition

Remedy

1.

Gears

 worn - rubbing

2.

Splines

 worn

3.

Primary gears

 worn - rubbing

4.

Bearings

 worn

5.

Bushing

 worn

1. Replace gears

2. Replace shaft(s)

3. Replace gears

4. Replace bearings

5. Replace bushing

Problem: Engine noisy (Noise seems to come from secondary-transmission/left-side cover)

Condition *

Remedy *

1.

Gears - shaft(s)

 worn

2.

Bearing(s)/bushing(s)

 damaged

1. Replace gears - shafts

2. Replace bearing(s)/bushing(s)

Problem: Engine noisy (Noise seems to come from secondary bevel gear and final driven shaft)

Condition

Remedy

1.

Drive - driven bevel gears

 damaged - worn

2.

Backlash

 excessive

3.

Tooth contact

 improper

4.

Bearing

 damaged

5.

Gears

 worn - rubbing

6.

Splines

 worn

7.

Final driven shaft thrust clearance

 too large

1. Replace gears

2. Adjust backlash

3. Adjust contact

4. Replace bearing

5. Replace gears

6. Replace shaft(s)

7. Replace thrust washer(s)

11-4

Problem: Clutch slipping

Condition *

Remedy *

1.

Release roller

 out of adjustment - 

loss of freeplay

1. Adjust clutch bolts 1 & 2

2.

Clutch springs

 weak

3.

Clutch shoes

 worn

4.

Pressure disc

 worn - distorted

5.

Clutch plates (driven - drive)

 distorted

2. Replace springs

3. Replace shoes

4. Replace disc

5. Replace plates

Problem: Clutch dragging

Condition *

Remedy *

1.

Clutch release roller

 out of adjustment - 

too much freeplay

1. Adjust clutch bolts 1 & 2

2.

Clutch springs

 weak

3.

Pressure disc - clutch plates

 distorted

4.

Clutch release mechanism

 worn - damaged

2. Replace springs

3. Replace disc - plates

4. Adjust - replace mechanism

Problem: Transmission will not shift

Condition *

Remedy *

1.

Gearshift cam

 broken

2.

Gearshift forks

 distorted

3.

Gearshift shaft

 worn

4.

Clutch release mechanism

 worn - damaged

5.

Reverse cable

 adjusted improperly

6.

Gearshift cable

 adjusted improperly

1. Replace cam

2. Replace forks

3. Replace shaft

4. Adjust - replace mechanism

5. Adjust cable

6. Adjust cable

Problem: Transmission will not shift back

Condition *

Remedy *

1.

Reverse shift cam

 broken

2.

Shift shafts

 rubbing - sticking

3.

Gearshift forks

 distorted - worn

4.

Gearshift lever return spring

broken - damaged

1. Replace cam

2. Repair shafts

3. Replace forks

4. Replace spring

Problem: Transmission jumps out of gear

Condition *

Remedy *

1.

Shifting gears (driveshaft - countershaft)

 worn

2.

Gearshift forks

 distorted - worn

3.

Cam stopper spring (gearshift cam)

 weak

4.

Gearshift lever stopper pin

 worn

1. Replace gears

2. Replace forks

3. Replace spring

4. Replace pin

Problem: Secondary-transmission will not shift or shift back

Condition *

Remedy *

1.

Sliding dog

 broken - worn

2.

Gearshift fork

 broken - worn

3.

Hi/Low shift lever

 out of adjustment

4.

Gearshift cam

 worn

5.

Cam stopper spring

 weak

6.

Gearshift fork shaft

 worn

1. Replace dog

2. Replace fork

3. Adjust lever

4. Replace cam

5. Replace spring

6. Replace shaft

RepairPro Service Manual

11-5

11

Problem: Engine idles poorly

Condition

Remedy

1.

Valve clearance

 out of adjustment

2.

Valve seating

 poor

3.

Valve guides

 defective

4.

Rocker arms - arm shaft

 worn

5.

Magneto

 defective

6.

CDI unit

 defective

7.

Spark plug

 fouled - 

gap

 too wide

8. 

Ignition coil

 defective

9.

Float

 out of adjustment

10.

Jets

 obstructed

11.

Pilot screw setting

 improper

1. Adjust clearance

2. Replace - service seats - valves

3. Replace guides

4. Replace arms - shafts

5. Replace magneto

6. Replace CDI unit

7. Adjust gap - replace plug

8. Replace ignition coil

9. Adjust float height

10. Clean jets

11. Adjust pilot screw

Problem: Engine runs poorly at high speed

Condition

Remedy

1.

High RPM “cut out”

 against RPM limiter

2.

Valve springs

 weak

3.

Valve timing

 out of adjustment

4.

Cams - rocker arms

 worn

5.

Spark plug gap

 too narrow

6.

Ignition coil

 defective

7.

Float level

 too low

8.

Air cleaner element

 obstructed

9.

Fuel hose

 obstructed

1. Shift into higher gear - decrease speed

2. Replace springs

3. Adjust timing

4. Replace cams - arms

5. Adjust gap

6. Replace ignition oil

7. Adjust float height

8. Clean element

9. Clean - prime hose

Problem: Exhaust smoke dirty or heavy

Condition

Remedy

1.

Oil (in the engine)

 overfilled - contaminated

2.

Piston rings - cylinder

 worn

3.

Valve guides

 worn

4.

Cylinder wall

 scored - scuffed

5.

Valve stems

 worn

6.

Stem seals

 defective

 1. Drain excess oil - replace oil

2. Replace - service rings - cylinder

3. Replace guides

4. Replace - service cylinder

5. Replace valves

6. Replace seals

11-6

Problem: Engine lacks power

Condition

Remedy

1.

Valve clearance

 incorrect

2.

Valve springs

 weak

3.

Valve timing

 out of adjustment

4.

Piston ring(s) - cylinder

 worn

5.

Valve seating

 poor

6.

Spark plug

 fouled

7.

Rocker arms - shafts

 worn

8.

Spark plug gap

 incorrect

9.

Carburetor jets

 obstructed

10.

Float level

 out of adjustment

11.

Air cleaner element

 obstructed

12.

Oil (in the engine)

 overfilled - contaminated

13.

Intake manifold

 leaking air

14.

Cam chain

 worn

1. Adjust clearance

2. Replace springs

3. Adjust timing

4. Replace - service rings - cylinder

5. Repair seats

6. Clean - replace plug

7. Replace arms - shafts

8. Adjust gap - replace plug

9. Clean jets

10. Adjust float height

11. Clean element

12. Drain excess oil - change oil

13. Tighten - replace manifold

14.  Replace cam chain

Problem: Engine overheats

Condition

Remedy

1.

Carbon deposit (piston crown)

 excessive

2.

Oil

 low

3.

Octane

 low - 

gasoline

 poor

4.

Oil pump

 defective

5.

Oil circuit

 obstructed

6.

Gasoline level (in float chamber)

 too low

7.

Intake manifold

 leaking air

8.

Coolant level

 low

9.

Fan

 malfunctioning

10.

Fan switch

 malfunctioning

11.

Thermostat 

stuck - closed

12.

Radiator hoses - cap

 damaged - obstructed

1. Clean piston

2. Add oil

3. Drain - replace gasoline

4. Replace pump

5. Clean circuit

6. Adjust float height

7. Tighten - replace manifold

8.  Fill - examine system for leaks

9. Check fan fuse - replace fan

10. Replace fan switch

11. Replace thermostat

12. Clear obstruction - replace hoses

RepairPro Service Manual

11-7

11

Drive

Problem: Power not transmitted from engine to wheels

Condition

Remedy

1.

Rear axle shaft serration

 worn - broken

1. Replace shaft

Problem: Power not transmitted from engine to either front wheel

Condition

Remedy

1.

Secondary drive - driven gear teeth

 broken

2.

Propeller shaft serration

 worn - broken

3.

Coupling

 damaged

4.

Coupling joint serration

 worn - damaged

5.

Front drive - driven bevel gears

 broken - 

damaged

6.

Front differential gears/pinions

 broken - 

damaged

7.

Sliding dog/shaft/fork

 worn - damaged

8.

Front drive axle

 worn - damaged

9.

Front drive axle serration

 worn - damaged

1. Replace gear(s)

2. Replace shaft

3. Replace coupling

4. Replace joint

5. Replace gear(s)

6. Replace gears - pinions

7. Replace gear(s)

8. Replace axle

9. Replace axle

11-8

Fuel System

Problem: Starting impaired

Condition

Remedy

1.

Starter jet

 obstructed

2.

Starter tube

 obstructed

3.

Starter body - carburetor

 leaking air

4.

Starter plunger

 not operating properly

1. Clean jet

2. Clean tube

3. Tighten - adjust - replace gasket

4. Check - adjust plunger

Problem: Idling or low speed impaired

Condition

Remedy

1.

Pilot jet - pilot air jet

 obstructed - loose

2.

Pilot outlet - bypass

 obstructed

3.

Pilot screw setting

 incorrect

4.

Starter plunger

 not fully closed

5.

Float height

 incorrect

1. Clean - tighten jet(s)

2. Clean outlet - bypass

3. Adjust pilot screw

4. Adjust plunger

5. Adjust float height

Problem: Medium or high speed impaired

Condition

Remedy

1.

High RPM “cut out”

 against RPM limiter

2.

Main jet - main air jet

 obstructed

3.

Needle jet

 obstructed

4.

Throttle valve

 not operating properly

5.

Filter

 obstructed

6.

Float height

 incorrect

7.

Starter plunger

 not fully closed

1. Shift into higher gear - decrease speed

2. Clean main jet - air jet

3. Clean needle jet

4. Check throttle valve operation

5. Clean filter

6. Adjust float height

7. Close plunger

Problem: Overflow and fuel level fluctuations

Condition

Remedy

1.

Needle valve

 worn - damaged

2.

Needle valve spring

 broken

3.

Float

 not working properly

4.

Needle valve

 dirty

5.

Fuel level

 too high - too low

1. Replace needle valve

2. Replace spring

3. Adjust float height - replace float

4. Clean needle valve

5. Adjust float height

RepairPro Service Manual

11-9

11

Electrical

Problem: Spark absent or weak

Condition

Remedy

1.

Ignition coil

 defective

2.

Spark plug

 defective

3.

Magneto

 defective

4.

CDI unit

 defective

5.

Pick-up coil

 defective

1. Replace ignition coil

2. Replace plug

3. Replace magneto

4. Replace CDI unit

5. Replace pick-up coil

Problem: Spark plug fouled with carbon

Condition

Remedy

1.

Mixture

 too rich

2.

Idling RPM

 too high

3.

Gasoline

 incorrect

4.

Air cleaner element

 dirty

5.

Spark plug

 incorrect (too cold)

1. Adjust carburetor

2. Adjust carburetor

3. Change to correct gasoline

4. Clean element

5. Replace plug

Problem: Spark plug electrodes overheat or burn

Condition

Remedy

1.

Spark plug

 incorrect (too hot)

2.

Engine

 overheats

3.

Spark plug

 loose

4.

Mixture

 too lean

1. Replace plug

2. Service cooling system

3. Tighten plug

4. Adjust carburetor

Problem: Magneto does not charge

Condition

Remedy

1.

Lead wires/connections

 shorted - loose - open

2.

Magneto coils

 shorted - grounded - open

3.

Regulator/rectifier

 shorted - punctured

1. Repair - replace - tighten lead wires

2. Replace magneto coils

3. Replace regulator/rectifier

Problem: Magneto charges, but charging rate is below the specification

Condition

Remedy

1.

Lead wires 

shorted - open - loose (at terminals)

2.

Stator coils (magneto) 

grounded - open

3.

Regulator/rectifier

 defective

4.

Electrolyte

 low

5.

Cell plates (battery)

 defective

1. Repair - tighten lead wires

2. Replace stator coils

3. Replace regulator/rectifier

4. Add distilled water

5. Replace battery

11-10

Problem: Magneto overcharges

Condition

Remedy

1.

Internal battery

 short circuited

2.

Regulator/rectifier resistor

 damaged - 

defective

3.

Regulator/rectifier

 poorly grounded

1. Replace battery

2. Replace resistor

3. Clean - tighten ground connection

Problem: Charging unstable

Condition

Remedy

1.

Lead wire

 intermittently shorting

2.

Magneto

 internally shorted

3.

Regulator/rectifier

 defective

1. Replace lead wire

2. Replace magneto

3. Replace regulator/rectifier

Problem: Starter button not effective

Condition

Remedy

1.

Battery charge

 low

2.

Switch contacts

 defective

3.

Starter motor brushes

 not seating

4.

Starter relay

 defective

5.

Emergency stop - ignition switch

 off

6.

Wiring connections

 loose - disconnected

1. Recharge - replace battery

2. Replace switch

3. Repair - replace brushes

4. Replace relay

5. Turn on switches

6. Connect - tighten - repair connections

Problem: Battery “sulfation” (Acidic white powdery substance or spots on surfaces of cell 
plates)

Condition

Remedy

1.

Charging rate

 too low - too high

2.

Battery electrolyte

 excessive - insufficient

3.

Specific gravity

 too high - too low

4.

Battery

 run-down - damaged

5.

Electrolyte

 contaminated

1. Replace battery

2. Keep electrolyte to prescribed level

3. Charge battery - add distilled water

4. Replace battery

5. Recharge - replace battery

Problem: Battery discharges too rapidly

Condition

Remedy

1.

Electrolyte

 contaminated

2.

Specific gravity

 too high

3.

Charging system (charging operation) 

not set 

properly

4.

Cell plates

 overcharged - damaged

5.

Battery

 short-circuited

6.

Specific gravity

 too low

7.

Electrolyte

 contaminated

1. Replace battery

2. Charge battery - add distilled water

3. Check magneto - regulator/rectifier - circuit 

connections - adjust for specified charging 
operation

4. Replace battery - correct charging system

5. Replace battery

6. Recharge battery

7. Replace battery

Problem: Battery polarity reversed

Condition

Remedy

1.

Battery

 incorrectly connected

1. Reverse connections - replace battery

RepairPro Service Manual

11-11

11

Steering/Suspension

Problem: Handling too heavy or stiff

Condition

Remedy

1.

Front wheel alignment

 incorrect

2.

Lubrication

 inadequate

3.

Tire inflation pressure

 incorrect

4.

Tie rod ends

 seizing

5.

Linkage connections

 seizing

1. Adjust alignment

2. Lubricate appropriate components

3. Adjust pressure

4. Replace tie rod ends

5. Repair - replace connections

Problem: Steering oscillation

Condition

Remedy

1.

Tires

 inflated unequally

2.

Wheel(s)

 wobbly

3.

Wheel hub cap screw(s)

 loose - missing

4.

Wheel hub bearing

 worn - damaged

5.

Tie rod ends

 worn - loose

6.

Tires

 defective - incorrect

7.

A-arm bushings

 damaged

8.

Bolts - nuts (frame)

 loose

1. Adjust pressure

2. Replace wheel(s)

3. Tighten - replace cap screws

4. Replace bearing

5. Replace - tighten tie rod ends

6. Replace tires

7. Replace bushings

8. Tighten bolts - nuts

Problem: Steering pulling to one side

Condition

Remedy

1.

Tires

 inflated unequally

2.

Front wheel alignment

 incorrect

3.

Wheel hub bearings

 worn - broken

4.

Frame

 distorted

5.

Shock absorber

 defective

1. Adjust pressure

2. Adjust alignment

3. Replace bearings

4. Repair - replace frame

5. Replace shock absorber

Problem: Steering impaired

Condition

Remedy

1.

Tire pressure

 too high

2.

Steering linkage connections

 worn

3.

Cap screws (suspension system)

 loose

1. Adjust pressure

2. Replace connections

3. Tighten cap screws

Problem: Tire wear rapid or uneven

Condition

Remedy

1.

Wheel hub bearings

 worn - loose

2.

Front wheel alignment

 incorrect

1. Replace bearings

2. Adjust alignment

Problem: Steering noise

Condition

Remedy

1.

Caps screws - nuts

 loose

2.

Wheel hub bearings

 broken - damaged

3.

Lubrication

 inadequate

1. Tighten cap screws - nuts

2. Replace bearings

3. Lubricate appropriate components

11-12

Brakes

Problem: Suspension too soft

Condition

Remedy

1.

Spring(s)

 weak

2.

Shock absorber

 damaged

1. Replace spring(s)

2. Replace shock absorber

Problem: Suspension too stiff

Condition

Remedy

1.

A-arm-related bushings

 worn

1. Replace bushing

Problem: Suspension noisy

Condition

Remedy

1.

Cap screws (suspension system)

 loose

2.

A-arm-related bushings

 worn

1. Tighten cap screws

2. Replace bushings

Problem: Rear wheel oscillation

Condition

Remedy

1.

Rear wheel hub bearings

 worn - loose

2.

Tires

 defective - incorrect

3.

Wheel rim

 distorted

4.

Wheel hub cap screws

 loose

5.

Axle shaft nut

 loose (Manual Transmission)

6.

Rear brake

 adjusted incorrectly

7.

Rear suspension arm-related bushing

 worn

8.

Rear shock absorber

 damaged

9.

Rear suspension arm nut

 loose

1. Replace bearings

2. Replace tires

3. Replace rim

4. Tighten cap screws

5. Tighten nut (Manual Transmission)

6. Adjust brake

7. Replace bushing

8. Replace shock absorber

9. Tighten nut

Problem: Braking poor

Condition

Remedy

1.

Pad

 worn

2.

Pedal free-play

 excessive

3.

Brake fluid

 leaking

4.

Hydraulic system

 leaking air

5.

Master cylinder/brake cylinder seal

 worn

1. Replace pads

2. Adjust free-play

3. Repair - replace hydraulic system

4. Bleed hydraulic system

5. Replace seal(s)

Problem: Brake lever travel excessive

Condition

Remedy

1.

Hydraulic system

 entrapped air

2.

Brake fluid

 low

3.

Brake fluid

 incorrect

4.

Piston seal - cup

 worn

1. Bleed hydraulic system

2. Add fluid to proper level

3. Replace with correct fluid

4. Replace seal - cup

Problem: Brake fluid leaking

Condition

Remedy

1.

Connection joints

 loose

2.

Hose

 cracked

3.

Piston seal

 worn

1. Tighten joints

2. Replace hose

3. Replace seal

RepairPro Service Manual