Yamaha F20A Manuel D'utilisation page 201

Trouble
C. Engine idles
irregularly or stalls.
Possible Cause
1. Spark plug(s) fouled or incorrect
type.
2. Fuel system obstructed.
3. Fuel contaminated or stale.
4. Fuel filter clogged.
5. Failed ignition parts.
6. Warning system activated.
7. Spark plug gap incorrect.
8. Poor connections or damaged
ignition wiring.
9. Specified engine oil not used.
10. Thermostat faulty or clogged.
11. Carburetor adjustments incorrect.
12. Fuel pump damaged.
13. Air vent screw on the fuel tank
closed.
14. Motor angle too high.
15. Carburetor clogged.
16. Fuel joint connection incorrect.
17. Throttle valve adjustment incorrect.
18. Battery lead disconnected.
1. Inspect spark plug(s). Clean or
replace with recommended type.
2. Check for pinched or kinked fuel
line or other obstructions in fuel
system.
3. Fill tank with clean, fresh fuel.
4. Clean or replace filter.
5. Have serviced by a Yamaha
dealer.
6. Find and correct cause of warning.
7. Inspect and adjust as specified.
8. Check wires for wear or breaks.
Tighten all loose connections.
Replace worn or broken wires.
9. Check and replace oil as specified.
10. Have serviced by a Yamaha
dealer.
11. Have serviced by a Yamaha
dealer.
12. Have serviced by a Yamaha
dealer.
13. Open the air vent screw.
14. Return to normal operating
position.
15. Have serviced by a Yamaha
dealer.
16. Connect correctly.
17. Have serviced by a Yamaha
dealer.
18. Connect securely.
5-2
GB
Remedy