EN
21
2. Low Gasoline Engine Power Output
Problem
Cause
Remedy
When turning throttle greater, speed increase
responds slowly or speed is decreased or
even engine stops running.
Ignition system
Fuel supply system
Incorrect ignition time
Air in fuel line or fuel line clogged
Main oil flow hole is not adjusted properly
In carburetor, needle valve hole and main
oil flow hole clogged
Fuel cock is clogged up
Too much carbon deposit in combusting
chamber
Readjust ignition advance angle
Exhaust air or dredge fuel line
Readjust
Clean and blow to get through
Clean, replace damaged part
Clear away
3. Gasoline engine cannot run smoothly
Problem
Cause
Remedy
Engine is pinking
Piston, cylinder or piston ring is worn excessively
Piston pin and piston pin hole are worn
Tie rod small head is worn excessively
Roller bearing for crankshaft main shaft is worn
Replace worn parts
Replace piston or piston pin
Replace tie rod
Replace roller bearing
Abnormal combustion
Engine is too hot
Too much carbon deposit in combustion chamber
Improper gasoline brand or low gasoline quality
Shoot trouble
Clear away
Replace with qualified gasoline
Engine cannot start because of spark lacking
There is water in float chamber
Improper spark plug electrodes clearance
Clean
Adjust
4. Engine stops suddenly when running
Problem
Cause
Remedy
Stops suddenly
when running
Fuel supply system
Fuel is used up
Carburetor is clogged
Float is leaking
Needle valve sticks
Refill fuel
Check fuel line and dredge
Repair
Dismantle float chamber & eliminate it
Ignition
system
Spark plug is struck through,
or short circuited by carbon deposit
Replace
spark plug
5. Gasoline engine is excessively hot
Problem
Cause
Remedy
Gasoline engine
is excessively hot
Improper ignition time
Insufficient fuel supply
Exhaust pipe is blocked up
Flow guard is leaking
Dirt or something like this fill up among air cooling fins
Cooling fan is loosen, losing function
Tie rod deformation makes piston and cylinder bushing side wear
Adjust ignition advance angle properly
Refill engine oil
Dredge exhaust pipe
Repair damaged part
Clear away dirt
Reinstall well
Replace tie rod
Note: the gasoline engine should run under a certain temparature. Generally, permitting temperature at the flow guard outlet is between 80 - 110
o
C, while
the temperature of the crankcase is about 60
o
C under the magneto. If the temperature surpasses the limits it is an indication that the gasoline engine is
excessively hot.
