MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
98
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
9. Abnormal Coolant Temperature, Lack of Coolant in the Diesel Engine Cooling
System
Phenomenon and Cause of Malfunction
Troubleshooting
Overheating
diesel engine
(1) Low coolant level (lack of coolant)
(2) Damage of the thermostat
(3) Thermostat valve unable to be
opened
(4) Malfunction of the water pump
(5) Malfunction of the oil supply system
(6) Damage of the radiator cap or
blockage of the radiator core
(7) Damage of the coolant temperature
sensor
(8) Coolant leakage caused by
damage of the cylinder gasket
(9) Damage of the thermostat
(10) Blockage of the cooling system
caused by foreign materials
(11) Open circuit of the cooling fan,
damage of the fan
(12) Blockage of the exhaust system
(13) Low engine oil level or unqualified
engine oil
(1) Refill coolant, check the cooling system for
leakage and repair it if necessary.
(2) Replace the thermostat device
(3) Replace the thermostat assembly
(4) Overhaul or replace the water pump
assembly.
(5) See Chapter 11 for troubleshooting the oil
supply system. (see Page 86~88)
(6) Replace the radiator cap or the wash
radiator.
(7) Replace the coolant temperature sensor.
(8) Replace the cylinder gasket.
(9) Replace the thermostat.
(10) Clean the cooling system.
(11) Replace the cooling fan circuit or the fan.
(12) Clean exhaust system.
(13) Add or replace the engine oil, adjust the
engine oil volume; it is recommended to use
API CI-4 or better oil from Mobil Oil
Corporation.
Too cold
diesel engine
(1) Damage of the thermostat valve or
the thermostat valve unable to be
closed
(2)
Malfunction
of
the
water
——thermometer
(1) Overhaul or replace the thermostat.
(2) Measure the coolant temperature and
replace the water thermometer.
Cooling
system lack
of water
(1) Leakage of the radiator
(2) Looseness of the radiator hose
connector or damage of the hose
(3) Leakage of the water pump
(4) Looseness of the heater hose
connector or damage of the hose
(1) Repair or replace the radiator.
(2) Screw up the radiator hose connector clip
or replace the hose.
(3) Overhaul or replace the water pump
assembly.
(4) Screw up the heater hose connector clip or
replace the hose.
Too long
preheating
time for the
diesel engine
(1) Damage of the thermostat
(2) Damage of the thermostat device
(1) Overhaul or replace the thermostat.
(2) Overhaul or replace the thermostat device.
