ENGINE OVERHEATS (Cont) - TM-9-2320-285-24-10056

TM 9-2320-285-24-1

2-11. COOLING SYSTEM TROUBLESHOOTING (CONT)

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

1. ENGINE OVERHEATS (Cont)

Step 10. Idle engine, remove radiator cap, and observe coolant. Check if coolant moves, indicating water pump

is operating.

a. If coolant does not move, notify direct support maintenance (refer to TM 9-2815-205-34 for repair or

replacement of water pump).

b. If coolant moves, go to step 11 below.

Step 11. With engine temperature below 180 degrees F, disconnect thermal switch lead at thermal switch (para

2-15e). Turn key switch to on position. Momentarily connect thermal switch lead to thermal switch; an

audible click should be heard at solenoid, indicating proper operation.

a. If audible click is heard, go to step 13 below.

b. If audible click is not heard, go to step 12 below.

Step 12. With engine temperature below 180 degrees F, and key switch turned to on position, use a voltmeter to

check for 12 Vdc at both terminals of thermal switch.

a. If voltage is present at both terminals, go to step 13 below.

b. If voltage is not present at one terminal, go to step 14 below.

c. If voltage is not present at either terminal, notify direct support maintenance.

Step 13. With key switch turned to off position, check continuity of solenoid using an ohmmeter: disconnect

ground wire from alternator (para 2-24) and unplug connector above left hand valve cover (para 2-15e).

a. If continuity is not obtained, replace solenoid (para 2-15e).

b. If continuity is obtained, go to step 14 below.

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