Suzuki EN125-2A, Service Manual

Page: 153 / 208

7-1 SERVICING INFORMATION
TROUBLESHOOTING
ENGINE
Complaint
Engine will not start
or is hard to start.
Engine stalls easily.
Noisy enigne.
Symptom and possible causes Remedy
Compression too low
Plug not sparking
No fuel reaching the carburetor
1. Valve clearance out of adjustment
2. Worn valve guides or poor seating of valves.
3. Valves mistiming.
4. Piston rings excessively worn.
5. Worn-down cylinder bore.
6. Poor seating of spark plug.
7. Starter motor cranks but too slowly.
1. Fouled spark plug.
2. Wet spark plug.
3. Defective pick up coil.
4. Defective ignitor unit.
5. Defective ignition coil.
6. Open or short circuit in high-tension cord.
1. Clogged hole in the fuel tank cap.
2. Clogged or defective fuel cock.
3. Defective carburetor float valve.
4. Clogged fuel pipe.
5. Clogged fuel filter.
Adjust.
Repair or replace.
Adjust.
Replace.
Replace or rebore.
Retighten.
Consult "electrical complaints"
Clean or replace.
Clean and dry.
Replace.
Replace.
Replace.
Replace.
Clean.
Clean or replace.
Replace.
Clean or replace.
Clean or replace.
1. Fouled spark plug.
2. Defective pick up coil.
3. Defective ignitor unit.
4. Clogged fuel pipe.
5. Clogged jets in carburetor.
6. Valve clearance out of adjustment.
7. Clogged fuel filter. Clean.
Replace.
Replace.
Clean.
Clean.
Adjust.
Clean or replace.
Excessive valve chatter
Noise appears to come from piston
Noise seems to come from clutch
Noise seems to come from crankshaft
1. Valve clearance too large.
2. Weakened of broken valve springs.
3. Worn down rocker arm or rocker arm shaft.
1. Piston or cylinder worn down.
2. Combustion chamber fouled with carbon.
3. Piston pin or piston pin bore worn.
4. Piston rings or ring groove worn.
1. Worn splines of countershaft or hub.
2. Worn teeth of clutch plates.
3. Distorted clutch plates, driven and drive.
4. Clutch damper weakened.
1. Worn of burnt bearings.
2. Bjg-end bearings worn and burnt.
3. Thrust clearance too large.
Adjust.
Replace.
Replace.
Replace.
Clean.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.