Engine over-
heats
1. Fuel/air mixture is thin
Adjust the carburetor
2. Cylinder covered with carbon deposit
Clean
Engine is noisy
or knocking
1. Fuel is bad
Replace the fuel
2. Firing chamber is covered with carbon deposit
Clean
3. Running parts worn or torn
Check and replace
Engine stops while running
Problem
Cause
Solution
Engine stops
suddenly
1. Piston is bitten
Replace the piston
2. Spark plug has carbon deposit or is short circuit-
ed
Clean carbon deposit
3. Magneto is damaged
Check and replace
Engine stops
slowly
1. Fuel is short
Fill the fuel tank
2. Carburetor is clogged
Clean
3. Water in fuel
Refill with fresh fuel
Engine is hard to stop
Problem
Cause
Solution
Engine
1. Cylinder and piston overheat due to self-ignition Clean carbon deposit
Correlative
circuit
1. Spark plug pole overheats
Clean the plug and
check the gap
2. Stop button is damaged
Check and replace
Problem and remedy of pump
Problem
Cause
Solution
Cannot self-
suck
1. No water or water shortage in pump
Feed water
2. Sealing of junction damaged or junction loosened
makes the suction hose suck in air
Replace or tighten
3. Suction hose is broken making air be sucked in
Replace the pipe
4. Valve connected on the discharge side is closed
or doubled
Check and adjust
5. Gap of impeller and volute shell is incorrect
Adjust
6. Pump clogged by foreign body
Clean
Water outlet is
insufficient
and pressure
is too low
1. Strainer of suction pipe clogged
Clean
2. Suction hose doubled or clogged
Clean
3. Pump clogged by foreign body
Clean
4. Impeller and volute shell worn out
Replace
5. Position of discharge port is too high
Change the location
of the pump
Cannot pull
the starter
1. Impeller and volute shell rusting
Clean
2. Pump is clogged
Clean
Leaking water
1. Mechanical seal worn out
Replace
2. O-sealing ring of pump shaft damaged
Replace
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