Part III Fault Judgement and Repair
13
3-1-5 Overheating of general-purpose gasoline engine
Phenomenon
Cause
Remedy
Gasoline engine
overheating
Insufficient oil
Fill sufficient oil
Exhaust port is blocked
Clean exhaust port
Leakage of air director
Repair damaged place
Sundries blockage in the middle of cooling fins
Clean cooling fins
Deformation of connecting rod causes the wears of the
piston and cylinder liner edge
Replace the connecting rod
Wears of cylinder, piston and piston ring causes air
leakage between cylinder and crankcase
Replace worn parts
Gasoline engine governor is improperly adjusted,
causing the speed to be too high
Re-adjust the governor
3-1-6 Abnormal sound
Phenomenon
Cause
Remedy
Knocking noise
Wear of piston, cylinder and piston ring
Replace worn parts
Wear of connecting rod, piston pin and pin hole
Replace worn parts
Wear of main journal of crankshaft
Replace the bearing
Piston ring is broken
Replace piston ring
Too large valve clearance
Adjust the valve clearance
Metal knocking
noise generates
during deflagration
Excessive carbon deposit in combustion chamber
Clear carbon deposit
Fuel label is incorrect
Replace fuel
Gasoline engine overheating
Find the cause and eliminate
Other
The valve clearance is improperly adjusted
Re-adjust the valve clearance
Loose connection between flywheel and crankshaft Reassemble
3-1-7 Failure of power generation of the generator
Phenomenon
Cause
Remedy
The generator
cannot generate
electricity
The collecting ring and the carbon brush are
contacted poorly
Clean the surface of the collecting
ring and grind the arc surface of the
carbon brush
The brush spring pressure is abnormal
Replace the spring or carry out
adjustment
Stator and rotor output wires of the generator
are contacted poorly The panel, instrument and
power socket are contacted poorly
Check that the winding connector is
reliable and the panel instrument
and power socket are correct, or
replace the defective parts.
Loss of excitation
Carry out charging
Check each winding for grounding or
breakdown
Check and insulate them one by
one.
Check the main winding and the excitation
circuit of the stator for open circuit.
Check and connect the open circuit
section by section.
AVR fault
Replace AVR