TM 5-3895-383-24
15.
No fuel to injectors:
a.
Check fuel level in the fuel tank and fill if necessary.
b.
Install new fuel filters if necessary. Blocked or
broken fuel lines should be cleaned or replaced.
c.
Defective fuel shutoff solenoid. Remove the fuel
shutoff solenoid from the governor. Energize the
start connection. If the plunger in the solenoid does
not move or fails to stay in the retracted position,
replace the solenoid.
d.
Check the fuel transfer pump for damage or wear
and make replacements as needed.
e.
Governor output shaft is not connected to the fuel
injector rack control (such as improper assembly
during overhaul). Make sure the linkage is correctly
engaged.
f.
Fuel injector rack control linkage is stuck in the fuel
shutoff position. Disconnect the governor output
shaft from the fuel injector control linkage. Make
sure the injectors are compressed slightly If the
rocker arms are removed, then check for binding.
Replace linkage as necessary.
g.
Malfunction within the governor. Perform a bench
test on the governor. Repair or replace the
governor if necessary. Bench test the repaired or
replacement governor.
16.
Exhaust system not open:
Loosen the exhaust pipe from the exhaust manifold.
If the engine will now start, check the exhaust
system for damage and/or restrictions.
17.
Solenoid does not energize:
18.
Low fuel pressure:
At starting rpm, the minimum fuel pressure for the
fuel transfer pump must be 20 kPa (3 psi) with
clean fuel filters. If the fuel pressure is less than 20
kPa (3 psi), look for air in the fuel supply line of the
transfer pump. If the fuel pressure is still low, check
the pressure regulating orifice and the fuel transfer
pump for correct operation. Repair as needed or
install new components.
19.
Bent clevis on governor:
Repair as needed or install new components.
20.
FRC setting too restrictive:
Check and make necessary adjustments.
Problem 4: Engine Misfiring Or Running Rough
Probable Cause(s):
Air In Fuel System
Leak Or Break In Fuel Line Between Transfer
Pump And Cylinder Head
Low Fuel Pressure
Fuel Has A High "Cloud Point"
Defect In Fuel Injector(s)
Valve Adjustment Not Correct
Fuel Injection Timing Not Correct
Bent Or Broken Pushrod
Fuel Injector Control Linkage Binding
Cylinder Head Gasket Leakage
Valve Leakage, Wear Or Damage To Pistons
And/Or Piston Rings, Wear Or Damage To
Cylinder Walls
Improper Injector Synchronization
Low Idle Rpm
Governor Control Group Linkage
Loose Or Missing Dash Pot Orifice Plug
1.
Air in fuel system:
With air in the fuel system the engine will normally
be difficult to start, run rough and release a large
amount of white smoke. Find the air leak in the fuel
system and correct it. If air is in the system, will
generally get in on the suction side of the fuel
transfer pump. Refer to Problem No. 39, Air In
Fuel.
2.
Leak or break in fuel line between transfer pump and
cylinder head:
Install a new fuel line.
3.
Low fuel pressure:
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.
6-34
