TM 5-6115-586-34
Section II. TROUBLESHOOTING
2-3. General
a. This section provides information useful in diagnosing and correcting' unsatisfactory operation or failure of the
power plant and its components. Malfunctions which may occur are listed in table 22. Each malfunction stated is
followed by a list of probable causes of the trouble. The corrective action recommended is described opposite the
probable cause.
b. Information concerning the use of special test equipment as an aid to troubleshooting is provided in paragraph 2-
4 of this section.
Table 2-2. Troubleshooting
Malfunction
Probable Cause
Corrective Action
1. Fuel boost pump motor assembly
a. Defective fuel boost pump motor
a. Check that 24 VDC is present at
fails to operate (batteries
assembly.
fuel boost pump connector P35.
charged)
If 24 VDC is present, repair or
replace pump (para 4-4); if
voltage is not present, continue to
step b.
b. Defective wire harness assembly.
2. Starter motor runs but does not
Defective starter motor clutch.
Repair or replace clutch (para 3-5).
rotate engine.
3. Engine stops motoring when
No-fuel relay (K44) defective.
Replace relay K44 (para 5-33).
master switch is released from
START to RUN position.
4. Engine motors but combustion
a. Low oil or depleted fuel supply.
a. Service power plant as required.
does not occur.
(see TM 5-6115-586-12.)
b. Fuel filter clogged or defective.
b. Clean, repair, or replace fuel filters
c.
Fuel control assembly failed.
c. Repair or replace fuel control
assembly (para 3-6).
e. Oil pressure sequencing switch
e. Replace oil pressure sequencing
failed.
switch. (see TM 5-6115-586-12).
f. Fuel atomizer screen obstructed.
f. Clean or replace screen (para 3-7).
5. Engine starts but will not ac-
a. Control air lines leaking.
a. Tighten or repair control air line
celerate to governed speed or
fittings (para 3-3).
accelerates too slowly.
b. Fuel control pump assembly
b. Repair fuel control pump (para 3-
failed.
6).
c. Fuel atomizer flow divider sticking
c. Repair fuel atomizer (para 3-71.
closed.
d. Remove and clean orificed fitting
plugged.
6. Engine lacks ability to carry load.
a. Fuel filter partially clogged.
a. Replace filter elements as required
b. Control air lines leaking.
b. Tighten control air lines fittings
c.
Fuel control failed.
7. Oil leaks from vent orifice of dual
Gearbox has positive pressure
Replace pump assembly on dual pad
pad gear box.
because of pump failure.
gear box (para 3-11 through 3-
13).
8. 60 Hz frequency meter out of
Defective meter.
Test meter and if faulty, replace
limits.
meter (para 5-26).
9. DC ammeter out of limits.
Improper adjustment.
Center zero adjustment (para 5-26).
10. DC ammeter does not indicate.
a. Damaged shunt.
b. Meter open.
11. Exhaust gas temperature meter
a. Replace thermocouple (see TM 5-
does not indicate.
thermocouple.
6115-586-12).
b. Open meter.
meter. (see TM 5-6115-586-12).
12. 60 Hz ammeter does not indicate
Defective meter.
Replace 60 Hz ammeter (para 5-26).
on either leg.
13. 60 Hz ammeter does not indicate
Open current transformer.
Replace current transformer (para 5.
on one leg.
26).
2-3
