Troubleshooting; Engine - Suzuki UF50 Service Manual

7-2 SERVICING INFORMATION

TROUBLESHOOTING

ENGINE

Complaint
Engine will not start
or is hard to start.
Engine stalls easily.
Engine is noisy.
Clutch slips.
Symptom and possible causes
Compression too low
1. Worn cylinder.
2. Worn piston ring.
3. Gas leaks from the joint in crankcase, cylinder or cylin-
der head.
4. Damaged reed valve.
5. Loose spark plug.
6. Broken, cracked or damaged piston.
Spark plug not sparking
1. Damaged spark plug.
2. Damaged spark plug cap.
3. Fouled spark plug.
4. Wet spark plug.
5. Defective ignition coil.
6. Defective stator coil.
7. Open or short in high-tension cord.
8. Defective ignition switch.
No fuel reaching the carburetor
1. Clogged hole in the fuel tank cap.
2. Clogged or defective fuel valve.
3. Defective needle valve.
4. Clogged fuel hose or defective vacuum hose.
1. Fouled spark plug.
2. Defective CDI unit.
3. Clogged fuel hose.
4. Clogged carburetor jet.
5. Clogged exhaust pipe.
Noise appears to come from piston
1. Worn down piston.
2. Worn cylinder.
3. Carbon built-up in the combustion chamber.
4. Worn piston pin, bearing or piston pin bore.
5. Worn piston rings or ring grooves.
Noise seems to come from crankshaft
1. Worn or burnt crankshaft bearings.
2. Worn or burnt big-end bearing.
Noise seems to come from final gearbox
1. Worn or rubbing final gears.
2. Worn splines.
3. Worn or damaged bearings of driveshaft or rear axle
shaft.
1. Worn or damaged clutch shoes.
2. Worn clutch drum.
Remedy
Replace.
Repair or replace.
Repair or replace.
Replace.
Tighten.
Replace.
Replace.
Replace.
Clean or replace.
Clean and dry or replace.
Replace.
Replace.
Replace.
Replace.
Clean or replace.
Clean or replace.
Replace with needle valve
seat.
Clean or replace.
Clean or replace.
Replace.
Clean.
Clean.
Clean.
Replace.
Replace.
Clean.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.