TM 9-2320-272-24-1
Table 2-2. Mechanical Troubleshooting (Contd).
13. ENGINE OIL CONTAMINATED
Step 1. Take oil sample to determine type of contamination(s) (para. 3-10).
Step 2. If excessive sludge is present in engine oil:
a. Review oil and filter change intervals (LO 9-2320-272-12).
b. Drain and refill engine crankcase (LO 9-2320-272-12).
NOTE
Perform step 3 for M939A2 series vehicles.
Step 3. If fuel is present in engine oil (thin, black oil is an indication):
a. Check transfer pump for leaking seal.
b. If leaking, replace transfer pump seal (para. 3-20).
Step 4. If coolant is present in engine oil (milky color):
NOTE
l During engine operation, oil pressure will be higher than
coolant pressure. A leak in oil cooler will indicate oil in coolant.
But, after engine is shut down, residual pressure in cooling
system will cause coolant to leak into oil.
l Perform step b. for M939A2 series vehicles.
a. Repair or replace oil cooler if leaking (para. 3-4, or notify DS maintenance).
b. Repair or replace aftercooler if leaking (para. 3-76).
Step 5. Check if metal particles are present in engine oil.
If metal particles are present, notify DS maintenance.
END OF TESTING!
14. EXCESSIVE VlBRATlNG OR CLUNKING
Step 1. Check engine mounting brackets and pads for looseness or damage.
a. If loose, tighten.
b. If engine mounting pad(s) are damaged, notify DS maintenance.
Step 2. Check vibration damper for looseness.
If vibration damper is loose, notify DS maintenance.
END OF TESTING!
15. EXCESSIVE FUEL CONSUMPTION
Step 1. Check air cleaner indicator for indication of air restriction.
a. If red appears at indicator window, inspect air intake stack for restrictions and, if
necessary, replace air cleaner element (TM 9-2320-272-10).
b. Beset air cleaner indicator by pressing button down.
Step 2. Inspect fuel lines and connections for leaks, breaks, obstructions, or damage.
a. Visually check for leaks. If leaks are present at connection, tighten.
b. If leaks are result of cracked, split, or damaged tubing, replace fuel line(s) (TM 9-243).
Step 3. Check fuel return line for bends and kinks.
Straighten or replace fuel return lines if bent or kinked.
END OF TESTING!
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