ARMY TM 9-6115-604-12
NAVY NAVFAC P-8-633-12
Table 4-3. Unit Troubleshooting (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
3.
ENGINE SHUTS DOWN SOON AFTER STARTING.
Step 1. Check OVERSPEED indicator.
Reset OVERSPEED indicator on annunciator panel reset speed switch SS1/SS2/SS3, and relatch air
control valves.
Step 2. Adjust FREQ ADJ rheostat R102 to minimize and attempt to restart.
If engine overspeeds, test, adjust, or replace speed switch SS1/SS2/SS3 as necessary.
4. ENGINE SHUTS DOWN AND WILL NOT RESTART.
Check safety circuits associated with shutdowns only low oil pressure switch, high coolant temperature switch,
coolant level switch, low fuel level, and speed switch.
Replace defective switches.
5. ENGINE RUNS ERRATICALLY OR MISFIRES.
Step 1. Check all fuel lines for bends, breaks, or loose fittings.
Repair or replace.
Step 2. Check air inlet filters and pipes.
Clear obstructions and/or replace filters as necessary. Check that air control valves are open
Step 3. Check turbochargers for dirt. Make sure turbocharger wheels turn freely
Replace If dirty
Step 4. Check fuel quality Drain a sample from the fuel tank into a clear container
Change fuel if cloudy. If fuel has water in it, change all filters
Step 5. Check valve lash and injector travel
Set valves and Injectors according to specifications. Refer to paragraph 4-81.
6. ENGINE EXHAUST EXCESSIVELY BLACK.
Step 1. Check engine fuel return line for obstruction
Correct as necessary.
Step 2. Check air intake system for obstructions or defective turbochargers.
Clear obstructions and replace defective components as necessary.
Step 3. Check for restricted fuel return lines or blocked fuel line vent.
Clear obstructions as required.
Step 4. Check air control valves.
Reset air control valves.
Step 5. Weather and altitude affect engine performance. If being operated In hot weather or at high altitude,
engine may be overloaded
Reduce load as required.
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