MAINTENANCE MANUAL OF ENGINE
144
14. Abnormal coolant temperature
Steps
Inspection
position
Fault causes
Troubleshooting
1
Overload
Overload operating time is too long.
It is operated within normal load
range.
2
Valve timing
The valve timing is not within speci-
fied range.
Adjust the valve timing:
Intake valve open Before upper dead
point 12±3°
Intake valve closed After lower dead
point 38±3°
Exhaust valve open Before lower
dead point 50±3°
Exhaust valve closed After upper dead
point 14±3°
3
Fuel supply
advance angle
The fuel supply advance angle is in-
sufficient.
Adjust the fuel supply advance angle
within 16°±1°
4
Cooling water
The water quantity is insufficient or
there is air in the water pipe.
Fill cooling water until the cooling
water level is over 5mm below the
sealing surface of the radiator cover,
or remove the air.
5
Water tank
The scale deposit on the water tank
and water passage is too much.
Clean the water tank
6
Water pump
There is water leakage from the water
pump or the fan belt is loosened.
Change the water pump or adjust the
belt tension (Through applying a force
about 98N to the middle part of the
belt, the sag is (7-9) mm for a new
belt, and (11-13) mm for a used belt).
7
Thermostat
The thermostat cannot be actuated
normally.
Replace the thermostat
8
Engine oil
The engine oil is insufficient or ex-
cessive, the engine oil pressure is too
low, the engine oil is thinned or dete-
riorated, or a wrong oil grade is used.
Fill engine oil above grade CD to the
specified level (5L-6L) as required.
9
Piston ring
and cylinder
liner
The piston ring is air-leaked, the pis-
ton and cylinder liner are worn ex-
cessively, and the gas goes into the
crankcase.
Replace it with a new one.
Summary of Contents for KM/4L22
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