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TROUBLESHOOTING PROCEDURES
2. POOR PERFORMANCE
Symptom
Possible cause
Remedy
The engine stalls when the speed is
increased.
The smoke is thin.
Backfiring
The fuel filter is clogged.
The fuel has run out.
The exhaust muffler is blocked with
oil deposits.
Clean the fuel filter and fuel lines.
Refuel the fuel tank.
Remove oil deposits.
Have the carburettor adjusted by an
authorized workshop.
Low compression
The piston, piston ring or cylinder is
worn.
Have the engine repaired by an
authorized workshop.
Engine leakage
The contact surface of the cylinder
and crankshaft leaks.
Have the engine repaired by an
authorized workshop.
Leakage of one of the crankshaft
seals.
Defective sealing.
Have the seal replaced by an
authorized workshop.
Engine overheats.
The combustion chamber is fouled
with oil deposits.
Avoid long-term operation at high
speed and high load.
Have the oil deposits removed by an
authorized workshop.
3. IRREGULAR ENGINE OPERATION
Symptom
Possible cause
Remedy
A metallic noise is heard.
The piston, piston ring or cylinder is
worn.
The piston or piston pin is worn.
The crankshaft bearing is worn.
Have the engine repaired by an
authorized workshop.
Have the engine repaired by an
authorized workshop.
Have the bearing replaced by an
authorized workshop.
A metallic noise is heard.
The engine overheats.
The combustion chamber is fouled
with oil deposits.
Unsuitable fuel.
Avoid long-term operation at high
speed and high load.
Have the oil deposits removed by an
authorized workshop.
Use gasoline of the correct octane
number.
The engine ignition misfires.
Water in fuel
Incorrect spark plug gap
Incorrect gap of the ignition coil
Change the fuel.
Adjust the gap
between the
electrodes of the spark plug to 0.6 -
0.7 mm.
Adjust the gap of the ignition coil to
0.3 - 0.4 mm.
4. ENGINE SUDDENLY STOPS
Possible cause
Remedy
The fuel has run out.
The spark plug is fouled with oil deposits and short-circuited.
The high-voltage cable is disconnected.
Refuel the fuel tank.
Have the oil deposits removed by an authorized
workshop.
Reconnect the high-voltage cable.
