5 Cooling System
DETROIT DIESEL 53
COOLING SYSTEM CAPACITY CHART
COOLANT DRAIN VALVES
Oil Cooler or
Side d Block
Side of Black
Fill Cooling System
Bottom of oil cooler,
Water hole cover
coolant inlet, and
between hand hold
Before starting the engine, close all of the drain cocks
side of block near
covers and side of
and fill the cooling system with water.
block near rear end
The use of clean, soft water will eliminate the need for
de-scaling solutions to clean the cooling system. A hard
mineral-laden water should be made soft by using water
softener chemicals before it is poured into the cooling
Drain Cooling System
system. These water softeners modify the minerals in
the water and greatly reduce or eliminate the formation
Drain the cooling system by opening the cylinder block
and radiator drain cocks and removing the cooling
system filler cap. Removal of the filler cap permits air
Start the engine and, after normal operating
to enter the cooling passages and the coolant to drain
temperature has been reached, allowing the coolant to
completely from the system.
expand to its maximum, check the coolant level. The
coolant level should be within 2 " of the filler neck.
Drain cocks are located as indicated the coolant drain
valve chart. Radiators that do not have-a drain cock are
Excessive amounts of air in the cooling system may
drained through the oil cooler housing drain.
hinder the flow of water due to pump cavitation or result
in hot spots when air collects at low velocity points in the
If freezing weather is anticipated and the engine is not
Therefore, whenever the cooling
protected by antifreeze, drain the cooling system
system is filled or make-up water is added, the air must
completely when the engine is not in use. Leave all of
be thoroughly vented from the system.
the drain cocks open until the cooling system is refilled.
Should any entrapped water in the cylinder block,
Should a daily loss of coolant be observed, and there
radiator or other engine parts freeze, it will expand and
are no apparent leaks, there is a possibility of gases
may result in damage to the engine.
leaking past the cylinder head water seal rings into the
cooling system. The presence of air or gases in the
cooling system may be detected by connecting a rubber
tube from the overflow pipe to a water container.
Bubbles in the water in the container during engine
operation will indicate this leakage. Another method for
observing air in the cooling system is by inserting a
transparent tube in the water outlet line.
1972 General Motors Corp.