TM 9-2320-272-24-1
Table 2-2. Mechanical Troubleshooting.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
ENGINE
1. ENGINE WILL NOT CRANK
NOTE
If STE/ICE is available, perform NG20 - No Crank - No Start Test
Step 1. Check battery and starting systems (Electrical Troubleshooting, para. 2-22).
Step 2. Remove starter (para. 2-82) and visually check starter drive and flexplate ring gear for
broken and missing teeth.
a. Replace starter if teeth are missing (para. 3-82).
b. If flexplate ring gear is damaged, notify DS maintenance.
c. Install starter (para. 3-82) if vehicle evacuation is required.
Step 3. Check belt-driven engine accessories for seizure.
a. Remove alternator, fan, water pump, and power steering pump drivebelts (para. 3-78,
3-70, 3-71, 3-67, and 3-230).
b. Manually turn drive pulley of each accessory.
c. Replace component if any accessory drive pulley will not turn (para. 3-80, 3-81, 3-71,
3-68, 3-67, and 3-236).
NOTE
Perform step 4 for M939A2 series vehicles.
Step 4. Check air compressor for seizure.
a. Remove air compressor (para. 3-206).
b. Rotate drive gear of air compressor. If drive gear does not turn, replace air compressor
c. Attempt to crank engine. If engine will not crank, notify DS maintenance.
Step 5. Check engine for fluid-locked pistons.
Remove turbocharger exhaust and air intake tubes (para. 3-21). If water is present, notify
DS maintenance.
END OF TESTING !
2. ENGINE CRANKS BUT WILL NOT START
NOTE
If STE/ICE is available, perform NG30 Engine Cranks No Start
Test (para. 2-24).
Step 1. Ensure emergency engine stop control is in all the way.
Step 2. Press accelerator pedal all the way down to floor and hold, then restart engine.
Step 3. Check air cleaner indicator for air restriction indications.
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. Reset air cleaner indicator by pressing button down.
NOTE
Perform steps 4 through 6 for M939A2 series vehicles.
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