Engine - Arctic Cat 650 Twin2004 Service Manual

Engine

Problem: Engine will not start or is hard to start (Compression too low)
Condition
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
Problem: Engine will not start or is hard to start (No spark)
Condition
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
Problem: Engine will not start or is hard to start (No fuel reaching the carburetor)
Condition
1. Gas tank vent hose obstructed
2. Carburetor inlet needle defective
3. Fuel hose obstructed
4. Fuel screens obstructed
5. Gas tank valve clogged or defective
6. Electric fuel pump defective
Problem: Engine stalls easily
Condition
1. Spark plug fouled
2. Magneto defective
3. CDI unit defective
4. Carburetor jets obstructed
5. Valve clearance out of adjustment
Problem: Engine noisy (Excessive valve chatter)
Condition
1. Valve clearance too large
2. Valve spring(s) weak - broken
3. Rocker arm - rocker arm shaft worn
4. Camshaft worn
11-2
Remedy
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
Remedy
1. Clean - replace plug
2. Clean - dry plug
3. Replace magneto
4. Replace CDI unit
5. Replace ignition coil
6. Replace high tension lead
Remedy
1. Clean vent hose
2. Replace needle
3. Clean - replace hose
4. Clean - replace inlet screen - valve screen
5. Clean - replace valve
6. Replace pump
Remedy
1. Clean plug
2. Replace magneto
3. Replace CDI unit
4. Clean jets
5. Adjust clearance
Remedy
1. Adjust clearance
2. Replace spring(s)
3. Replace arm - shaft
4. Replace camshaft