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4-1-6 Abnormal sound
Phenomenon
Cause
Remedy
Knocking noise
Wear of piston, cylinder and piston ring
Replace worn parts
Wears of piston, cylinder and piston
ring
Replace worn parts
Piston ring is broken
Replace piston ring
Produce metal
knocking sound
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
Reinstall
4-2 Pre-maintenance Preparations
4-2-1 Safety factors
Failure of observing the following precautions will cause the void of warranty commitment
provided with gasoline engine, and it may damage the gasoline engine or cause personal
injury. Therefore, before operating gasoline engine, the user shall pay special attention to
following points:
1) Strictly carry out the matching according to power shown on the nameplate. It is
strictly forbidden to operate under overload and over-speed condition or low load and low
speed for a long term.
2) Apply fuel and oil with code designation, which must be fully precipitated and filtered
before use. Refueling appliance shall be maintained clean, and the oil shall be replaced
regularly.
3) Check the tightness of fastening bolts of the gasoline engine regularly, and tighten
them in time.
4) Replace the air filter element every 50 h.
5) This engine is air-cooled gasoline engine, so the debris and dirt on cooling fins, air
