TM 9-2320-272-24-2
Table 4-1. Mechanical Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
22. ENGINE OVERSPEED
Replace or repair fuel pump (para. 4-35 or 4-57).
END OF TESTING!
23. ENGINE LUBRICATING OIL DILUTED BY FUEL
Perform malfunction 2.
END OF TESTING!
24. ENGINE FUEL KNOCKS
Step 1. Check fuel injectors for proper operation and adjustment, Notify General Support
maintenance.
Step 2. Check valve and injector timing adjustment (para. 4-32 or 4-56).
NOTE
Perform step 3 for M939A2 series vehicles.
Step 3. Check fuel injection pump timing. Notify General Support maintenance.
END OF TESTING!
COOLING SYSTEM
25. ENGINE OVERHEATS
Step 1. Check for proper operation of fan drive clutch. Replace fan drive clutch if malfunctioning
(para. 4-61 or 4-62).
Step 2. Check water pump for wear or damage. Repair or replace water pump if worn or damaged
(para. 4-63 or 4-29).
END OF TESTING!
26. LOSS OF COOLANT
Perform malfunction 8, step 2.
END OF TESTING!
27. CONTAMINATED COOLANT
Perform malfunction 8, step 2.
END OF TESTING!
TRANSMISSION
28. TRANSMISSION SHIFTS OCCUR AT TOO HIGH A SPEED
Step 1. Check governor pressure (para. 5-60).
If malfunction is not corrected, proceed to step 2.
Step 2. Adjust modulator linkage (para. 3-145).
If malfunction is not corrected, replace transmission (para. 4-71).
END OF TESTING!
29. TRANSMISSION SHIFTS OCCUR AT TOO LOW A SPEED
Perform malfunction 1.
END OF TESTING!
4-9
