COOLING SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
COOLING SYSTEM CHECK (ENGINE AND COOLING SYSTEM HEAT PROBLEMS)
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· Use a container to catch any fluid that may drain from hoses or system. Dispose of fluid IAW local policy and
ordinances. Ensure all spills are cleaned up.
· The following conditions indicate that a heat problem exists:
Hot coolant is released through filler cap during normal engine operation. Hot coolant is also
released when engine is stopped.
Hot coolant is released from cooling system but not through filler cap during normal
operation of engine.
Coolant must be added frequently to cooling system. Coolant is not released through filler cap
or through outside leak.
· Running engine at medium idle will allow engine to cool before engine is stopped.
Run engine at medium idle (approximately 1,200 rpm) for three minutes after high idle shuts off (TM 5-3805-290-10).
Refer to Checking Filler Cap in this work package to determine if filler cap is damaged.
Refer to Testing Radiator and Cooling System for Leaks (Pressure Test), in this work package to check for cooling sys-
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Engine may overheat if high idle rpm is set too high.
If coolant does not flow though radiator and other components of cooling system, perform these procedures:
Service cooling system (WP 0042 00).
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Compressed air may be used to remove materials from cooling system. Detergent added to water may also
be used. Identify cause of restriction before choosing method for cleaning.
Clean radiator and other components with hot water or steam at low pressure.
Straighten any bent radiator fins or replace radiator as necessary (WP 0167 00).
TESTING RADIATOR AND COOLING SYSTEM FOR LEAKS (PRESSURE TEST)
When engine has cooled, loosen filler cap to first stop. Allow any remaining pressure to release from cooling system.
Make sure coolant covers top of radiator core (WP 0042 00).
Pressurize cooling system with cooling system pressure tester to 3 psi (20 kPa) more than operating pressure of filler
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Radiator and cooling system DO NOT have leakage if no leakage is observed after five minutes and
pressurizing pump gage remains constant for five minutes or more.
Inside of cooling system has leakage only if reading on pressurizing pump gage goes down and no out-
side leakage is observed or outside leakage is observed.
Check outside of radiator for leakage. Replace radiator if necessary (WP 0167 00).
Check all connections and hoses of cooling system for leaks. Make any repairs, as required.
If reading on pressurizing pump gage goes down and no outside leakage is observed, refer to WP 0146 00 to inspect or
replace cylinder head gasket or head as necessary.
END OF WORK PACKAGE