TM 5-3805-290-23-1
COOLING SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0012 00
12
12
WARN I N G
DO NOT service cooling system unless engine has been allowed to cool down. This is a pressurized cooling sys-
tem and escaping steam or hot coolant may result in serious burns.
DO NOT remove cooling system radiator cap when engine is hot. Allow engine to cool down. Loosen cap to
first stop and let any pressure out of cooling system, then remove cap. Failure to follow this warning may
result in serious burns.
Wear effective eye, hand, and skin protection when handling coolants. Failure to do so may result in injury to
personnel.
Cooling system conditioner contains alkali. Avoid contact with skin and eyes.
N OT E
Coolant must be at correct level to check cooling system (TM 5-3805-290-10). Engine must be cool and not
running. After engine is cool, the radiator filler cap can be loosened to relieve any remaining pressure from
cooling system.
Level of coolant should not be more than 0.5 in. (13 mm) from bottom of filler pipe. If cooling system is
equipped with sight glass, coolant should be at proper level in sight glass.
Engine has pressure-type cooling system. Pressure-type cooling systems give two advantages. They can oper-
ate safely at higher temperatures than boiling point of water at range of atmospheric pressures. They also
reduce cavitation in water pump.
Cavitation is formation of bubbles in liquids by mechanical forces. Forming of air bubbles or steam pockets is
much less common in pressure-type cooling systems.
Regular inspections of cooling system should be made to identify problems before damage can occur. Visually
inspect cooling system before tests are made with test equipment.
For a better understand of each system, review the appropriate section in Theory of Operation (WP 0003 00).
0012 00-2
