Engine Overheat; Too Much Engine-Oil Consumption; Speed Increased Greatly; Engine Stops By Itself - FAW Jiefang Automotive 485 Operation & Maintenance Manual

Trouble causes
1. Fuel enters into crankcase; or engine-oil is
mixed by water, it becomes thinner; too much
or less engine-oil; low flow-rate and pressure of
engine-oil; fit clearance of bearing is too small.
2. Water pump impeller is damaged and broken,
and fan belt slips; positions of heat radiator and
fan are improper; thermostat is failure; cooling
system piping is clogged; too thick water-scale
in water jacket; water pump displacement is not
enough; cylinder cover gasket is broken and
fuel gas enters water-passage.
1. The viscosity of the oil used is too low, or the
brand is not correct.
2. Piston and cylinder jacket is severely worn;
oil-return hole on piston ring groove is clogged.
3. Piston ring is stuck by glue; gas ring if fitted
with upper and lower faces being reversed; too
much wearing
4. Oil leaks on crankshaft front/rear oil-seal,
crankcase sump joint plane and side cover etc.
5. Engine-oil temperature or pressure is too
high, or evaporated and splashed.
1. Speed governor is failure, and pull-rod is
jammed at "large oil flow-rate" position.
2. Speed governor's sliding disc shaft sleeve is
jammed.
3. Adjust-arm is released from shifting fork.
1. Air in oil-passage; oil-transfer pump does not
supply oil; diesel oil filter is clogged.
2. Piston is jammed in cylinder; journal is
jammed by bush.
3. Fuel-injection oil-delivery valve is jammed;
plunger spring is broken; speed governor
sliding disc sleeve is jammed.
VII. Engine overheat
VIII. Too much engine-oil consumption
IX. Speed increased greatly
X. Engine stops by itself
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Remedial methods
1. Inspect and replace piston ring; change
engine-oil; inspect oil level; inspect wearing
conditions of inner/outer rotor; inspect and
adjust the fit clearance of each bearing.
2. Inspect and replace the impeller; inspect
the belt's tightness or replace the belt;
inspect the position of heat radiator; inspect
the working condition of thermostat; clean
the cooling system and water jacket; inspect
the clearance of impeller; fill fully water;
replace the cylinder cover gasket.
1. The oil, the brand of which is specified (in
this Manual), should be used.
2. Replace; clean the oil-return hole.
3. Clean or replace it.
4. Inspect or replace them, if necessary.
5. Reduce the temperature (see previous
section); inspect
pressure-limit valve of engine-oil pump.
1. Inspect and repair the speed governor and
its pull-rod.
2. Inspect and repair it.
3. Inspect and repair it.
1. Discharge the air; inspect and repair
oil-transfer pump; clean diesel oil filter.
2. Fit clearance is not correct; repair and
replace it.
3. Inspect, repair or replace it.
and adjust the