15.2 Trouble Shooting Engine
DETROIT DIESEL 53
1. The cooling system should be cleaned with a good
Check the flow of water through the radiator. A clogged
cooling system cleaner and thoroughly flushed to
radiator will cause an inadequate supply of water on the
remove scale deposits.
suction side of the pump. Clean the radiator core,
Remove the radiator cap and operate the engine,
The exterior of the radiator core should be cleaned to
checking for combustion gases in the cooling system.
open plugged passages permitting normal air flow.
The cylinder head must be removed and inspected for
cracks and the head gaskets replaced if combustion
Loose fan belts should be adjusted to the proper
gases are entering the cooling system.
tension to prevent slippage.
Check for an air leak on the suction side of the water
Check for an improper size radiator or inadequate
pump. Replace defective parts.
3. The thermostat may not be closing. Remove,
Repair or replace inoperative temperature-controlled
inspect and test the thermostat. Install a new thermostat
2. Check the coolant level and fill to the filler neck if
Check for an improperly installed heater.
the coolant level is low.
4. Excessive leakage of coolant past the thermostat
Inspect for collapsed or disintegrated hoses. Replace
seal(s) is a cause of continued low coolant operating
all faulty hoses.
temperature. when this occurs, replace the thermostat
Thermostat may be inoperative. Remove, inspect and
test the thermostat; replace if found faulty.
Check the water pump for a loose or damaged
1970 General Motors Corp.