ARMY TM 9-6115-604-12
NAVY NAVFAC P-8-633-12
SECTION V. TROUBLESHOOTING
a. Table 4-3 contains troubleshooting information for locating and correcting operating troubles which may develop in the
generator set Each malfunction for an individual component unit, or system, is followed by a list of tests or inspections
which will help you to determine probable cause and corrective actions to take Perform the tests, inspections, and
corrective actions In the order listed
b. Troubleshoot In accordance with Table 3-3 before using Table 4-3. Use Table 4-3 only if the operator inspections,
test, and corrective actions fall to restore the generator set to an operational condition
c This manual cannot list all malfunctions that may occur, nor all tests or Inspections and corrective actions If a
malfunction cannot be corrected by listed corrective actions, notify your supervisor
Table 4-3. Unit Troubleshooting
TEST OR INSPECTION
ENGINE FAILS TO CRANK.
Step 1. Check annunciator panel for lit OVERSPEED indicator.
If OVERSPEED Indicator is lit, reset OVERSPEED indicator on annunciator panel, reset speed
switch SS1/SS2/SS3, and relatch air control valves.
Step 2. Check for 24 V dc at starter solenoids.
If 24 V dc is not present, check wiring (refer to FO-1)
If 24 V dc is present, replace starter relays.
Step 3. Bar over engine and If It turns freely, check starter motor amperage draw Refer to paragraph 4-33.
Replace starter motors If amperage draw exceeds 120 amperes
Step 4. Check for proper operation of starter motors.
Replace starter motors If defective
ENGINE CRANKS BUT WILL NOT START.
Step 1. Check fuel solenoid valve and fuel filters.
Check power to fuel solenoid valve on Injection pump and check for plugged fuel filters.
Replace plugged fuel filters.
Step 2. Check emergency manual fuel shut off valve.
Make sure that the push/pull emergency control is pushed In.
Step 3. Check air supply to engine.
Remove obstructions Replace clogged filters. Check that air control valves are open.
Step 4. Step 4 Check starter motor current draw. Refer to paragraph 4-33.
Replace starter if defective.