Troubleshooting; Engine - Suzuki LT-Z90 Manual

7-2 SERVICING INFORMATION

TROUBLESHOOTING

ENGINE

ENGINE WILL NOT START OR IS HARD TO START
Symptom, possible causes and remedy
1) Compression too low
• Valve clearance out of adjustment.
• Worn valve guides or poor seating of valves.
• Mistimed valves.
• Excessively worn piston rings.
• Worn-down cylinder bore.
• Starter motor cranks too slowly.
• Poor seating of spark plug.
• Gas leaks from the joint in cylinder or cylinder
head.
• Loose spark plug.
• Broken, cracked or damaged piston.
2) Plug not sparking
• Fouled spark plug.
• Wet spark plug.
• Defective CKP sensor
• Defective CDI unit.
• Defective ignition coil.
• Open-circuited wiring connections.
• Defective generator coil.
3) No fuel reaching the carburetor
• Clogged fuel hose.
• Clogged or defective fuel valve.
• Defective carburetor needle valve.
• Clogged fuel filter.
ENGINE STALLS OFTEN
Symptom, possible causes and remedy
• Fouled spark plug.
• Defective CDI unit.
• Defective ignition coil.
• Clogged fuel hose.
• Clogged carburetor jets.
• Clogged exhaust pipe.
• Damaged cylinder head gasket.
• Valve clearance out of adjustment.
Adjust.
Repair or replace.
Adjust.
Replace.
Replace.
See electrical section.
Retighten.
Repair or replace.
Tighten.
Replace.
Clean or replace.
Clean and dry.
Replace.
Replace.
Replace.
Repair or replace.
Replace.
Clean or replace.
Clean or replace.
Replace.
Clean or replace.
Clean.
Replace.
Replace.
Clean.
Clean.
Clean.
Replace.
Adjust.