Engine troubleshooting
For the engine to operate normally, the following four conditions must be met:
1. Good fuel: there is a certain ratio of combustible mixture in the cylinder.
2. Good spark: The spark plug gives off a strong spark at the right time.
3. Sufficient compression: there is enough compression pressure in the cylinder.
4. Valve timing: correct valve opening time.
Engine failure, can focus on the above four aspects, check, analyze the cause of the failure, and to eliminate.
Fault performance
Inspection method
Inspection result
Possible cause
The engine will not start
or has difficulty starting
Check for fuel flow into
carburetor
No fuel flow into the
carburetor
No fuel in the tank
The fuel line from tank to
carburetor is blocked
Fuel
flows
into
the
carburetor
The float assembly in the
carburetor is stuck
The vent on the tank cap
is blocked
Remove the spark plug to
test the spark
The spark is weak or
completely absent
Spark plug failure
Spark plug is not clean
The electronic ignition is
faulty
The magneto is out of
order
The spark is good
The connection is bad
and broken
The high-voltage cable is
disconnected
or
short-circuited
The
ignition
coil is
disconnected
or
short-circuited
The ignition switch is
faulty
Test cylinder pressure
The pressure is too low
The starting mechanism
skidded and failed to turn
the engine
The pressure is normal
Valve clearance is too
small
Valve opening blocked
Cylinder or piston ring
wear
The cylinder head gasket
is broken
Improper valve timing
Restart the engine
The engine ignites but
will not start
Choke opens too large
Carburetor
trimmer
screw
not
properly