CF MOTO CF500-5, Service Manual

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14-6
CFMOTO
Engine Troubleshooting
1. Engine
Complaint Symptom and Possible Causes Remedy
Engine will not
start or is hard to
start
Compression is Too Low
1. Worn cylinder
2. Worn piston ring
3. Leakage with cylinder gasket
4. Wear valve guide or improper valve
seating
5. Loose spark plug
6. Slow cranking of starting motor
7. Faulty
valve timing
8. Improper valve clearance
No Sparking from Spark Plug
1. Fouled spark plug
2. Wet
spark plug
3. Defective ignition coil
4. Open or short circuit with pickup coil
5. Faulty
generator
6. Faulty CDI
No Fuel Reach Into Carburetor
1. Clogged fuel tank vent tube
2. Clogged or faulty fuel valve
3. Faulty carburetor needle valve
4. Clogged fuel hose
5. Clogged fuel filter
Transfer is not in Neutral position
Replace
Replace
Replace
Repair or Replace
Tighten
Check electrical part
Adjust
Adjust
Clean or Replace
Clean and dry or replace
Replace
Replace
Replace
Replace
Clean or Replace
Clean or Replace
Replace
Replace
Clean or Replace
Set to Neutral position
Engine stalls easily
or has unstable
idle speed
1. Improper valve clearance
2. Improper valve seating
3. Faulty valve guide
4. Worn rocker arm or rocker arm shaft
5. Fouled spark plug
6. Improper spark plug gap
7. Faulty ignition coil
8. Faulty
CDI
9. Faulty generator
10. Improper fuel level in float chamber
11. Clogged carburetor jet
12. Faulty fuel valve
13. Improper adjustment or idle screw
Adjust
Replace or Correct
Replace
Replace
Replace
Replace or Adjust
Replace
Replace
Replace
Adjust Fuel level
Clean
Replace
Adjust