18
Needle
valve
is
not
closed properly or start
hole is clogged.
Dismantle needle valve and repair, clean,
blow to get through.
supply.
Float is damaged or
sticking.
Repair float
Fuel is too filthy or
deteriorated
Replace
There is water in fuel
Replace
Too much fuel in engine
Drain extra fuel, dry up spark plug
electrodes
1. Normal cylinder
compression.
2. Normal spark plug
spark.
3. Something wrong
with the fuel
system.
4. Smooth fuel flow.
Wrong fuel brand
Select proper fuel brand corresponding
with the requirements
Too much carbon deposit
and dirt around
electrodes.
Clear away
Electrodes are burn
damaged seriously or
insulators damaged
Replace spark plug
1. Normal cylinder
compression.
2. Normal fuel
supply.
3. Normal
high-pressure coil
spark.
4. Spark plug is in
bad conditions.
Improper electrodes gap
Adjust to proper value
High-pressure coil is
damaged
Replace
Ignition coil is damaged
Replace
1. Normal cylinder
compression.
2. Normal fuel
supply.
3. No high-pressure
coil spark.
4. Normal spark
plug.
Magneto loses
magnetism
Replace
Piston ring is worn to or
even over its wear limit
Replace
Piston ring is broken
Replace
Piston ring is sticking
Clear up carbon fouling
Spark plug is not installed
tighten or without a
gasket
Tighter with a gasket in
Air leakage between
cylinder block and
cylinder head
Check cylinder gasket, and the flatness of
the surface by which cylinder block
contacting with cylinder head, tighten
cylinder head bolts in stipulated order to
stipulated torque.
1. Poor cylinder
compression.
2. Normal fuel
supply system.
3. Normal ignition
system.
Air leakage in valves
Check valve, clearance and tightness,
repair if necessary
WARNING:
●
When testing the spark plug, never hold the high-voltage wire of the spark plug with wet hand.
