TM 5-3895-383-24
1.
Fuel pressure is low:
Make sure there is fuel in the fuel tank. Look for
leaks or bad bends in the fuel line between fuel tank
and fuel transfer pump. Look for air in the fuel
system. (if fuel in the fuel tank cannot be checked
for air, install a sight tube in the fuel line). Make sure
the fuel filters are clean, then check fuel pressure.
The outlet pressure of the fuel transfer pump must be
a minimum of 200 kPa (29 psi) at full load speed. If
fuel pressure is lower than the above pressure,
check the fuel transfer pump and fuel pressure
regulating orifice at the fuel return line.
2.
Engine misfiring:
Refer to Problem No. 4, Engine Misfiring Or
Running Rough.
3.
Fuel injector control linkage is binding:
Disconnect the governor output shaft from the fuel
injector rack control linkage. Check the linkage for
smooth movement. If linkage still appears to be
binding, remove injectors. With injector springs
compressed,
check
injector
racks
for
smooth
operation. Replace injectors with "sticky" racks. Check
linkage again for smooth operation. If still binding,
loosen bolts holding linkage to cylinder head. Operate
the linkage by hand. If binding is still present after
retightening the bolts, replace the control linkage.
4.
Improper injector synchronization:
Check and make necessary adjustments as per
Testing and Adjusting Section of the Service
Manual.
5.
Problem with the governor:
Bench test the governor. If the governor cannot be
properly adjusted during bench testing, repair or
replace the governor. Bench test the repaired or
replacement governor.
Problem 10: Engine Overspeeds On Start
Fuel Control Linkage
Governor Problem
1.
Fuel control linkage:
Improper assembly after overhaul, linkage not free,
stuck in fuel-on position, governor output shaft not
connected to fuel injector control linkage. Make repairs
or replacements as needed.
2.
Governor problem:
Bench test the governor. If the governor cannot be
properly adjusted during bench testing, repair or
replace the governor. Bench test the repaired or
replacement governor.
Problem 11: Too Much Vibration
Probable Cause(s):
Vibration Damper Loose
Vibration Damper Has A Defect
Engine Supports Are Loose, Incorrect Or Have A
Defect
Driven Equipment Is Not In Alignment Or Is Out Of
Balance
Misfiring Or Running Rough
Improper Injector Synchronization
1.
Vibration damper loose:
Check vibration damper for damage. Tighten bolts.
If vibration damper bolt holes have damage or
wear, replace with new parts.
2.
Vibration damper has a defect:
Install a new vibration damper.
3.
Engine supports are loose, incorrect or have a defect:
Tighten all mounting bolts. Install new components
if necessary.
4.
Driven equipment is not in alignment or is out of
balance:
Check alignment and balance, correct if needed.
5.
Misfiring or running rough:
Rear to Problem No. 4, Engine Misfiring Or
Running Rough.
6.
Improper injector synchronization:
Check and make necessary adjustments as per
Testing and Adjusting Section of the Service
Manual.
Problem 12: Loud Combustion Noise (Sound)
Probable Cause(s):
Air In Fuel System
Low Quality Fuel
Incorrect Fuel Injection Timing Dimension
Improper Injector Synchronization
Defect In Fuel Injector(s)
Mechanical Problem
6-39
