3. TROUBLESHOOTING
23
3-1-3 Speed Unstable
TROUBLE
CAUSE
REMEDY
Knocking sound
Piston, cylinder or piston ring is worn excessively. Replace the worn
Piston pin and piston pin hole are worn excessively. Replace piston or piston pin
Tie rod small head is worn excessively.
Replace tie rod
Abnormal
combustion
Engine is too hot
Shoot trouble
Too much carbon deposit in combustion chamber
Clear away
Improper gasoline brand or low gasoline quality
Replace with qualified gasoline
Spark lacking
There is water in float chamber
Clean
improper spark plug electrodes clearance
Adjust
Something wrong with induced coil, and so on
Check and replace damaged parts
3-1-4 Unable Igniting
TROUBLE
CAUSE
REMEDY
Unable
igniting
Fuel supply
system
Fuel is finished
Refill fuel
Carburetor is clogged
Check fuel line and dredge
Float is leaking
Repair
Needle valve is sticked
Dismantle
float
chamber
and
eliminate it
Ignition system
Spark
plug
is
punctured,
or
short-circuited by carbon deposit
Replace spark plug
Side electrode of spark plug is dropped
out
Replace spark plug
High-tension wire is dropped out
Weld on
Ignition
coil
is
punctured
or
short-circuited
Replace ignition coil
Parking wire is located on engine body Find out meeting and insulate
The other
Cylinder is seriously scored and valve
dropped out
Repair or replace damaged parts