Suzuki DR 125, Service Manual

Page: 160 / 222

7-2 SERVICING INFORMATION
TROUBLESHOOTING
ENGINE
Complaint Symptom and possible causes Remedy
Engine will not start
or is hard to start. Compression too low
1. Worn cylinder.
2. Worn piston ring.
3. Worn valve guide or improper valve seating.
4. Loose spark plug.
5. Broken, cracked, or damaged piston.
6. Mistimed valves.
7. Valve clearance out of adjustment.
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. Open or short in high-tension cord.
7. Defective generator.
8. Defective CDI unit.
No fuel reaching the carburetor
1. Clogged fuel tank vent hose.
2. Clogged or defective fuel valve.
3. Defective carburetor needle valve.
4. Clogged fuel hose.
5. Clogged fuel filter.
Replace.
Replace.
Repair or replace.
Tighten.
Replace.
Adjust.
Adjust.
Replace.
Replace.
Clean or replace.
Clean and dry or replace.
Replace.
Replace.
Replace.
Replace.
Clean or replace.
Clean or replace.
Replace.
Clean or replace.
Clean or replace.
Engine stalls easily. 1. Fouled spark plug.
2. Defective generator.
3. Defective CDI unit.
4. Clogged or defective fuel valve.
5. Clogged carburetor jet.
6. Valve clearance out of adjustment. Clean or replace.
Replace.
Replace.
Clean or replace.
Clean.
Adjust.