TM 5-3810-307-24-1-2
Table K-5. Impact Hammer Troubleshooting (Continued)
Symptom
Probable Cause
Corrective Action
Fuel Pump
1.
Remove the inlet fuel line (flexible rubber
The fuel pump does not
1.
Possible air-lock in fuel pump.
hose) and insert a clean 1/8-inch (3 mm)
operate properly.
rod into the passage to depress the inlet
check valve (the inlet check valve
operates by a very light spring). Fill the
inlet with fuel and depress the check
valve. Continue filling until no bubbles
appear. Reconnect the inlet fuel line.
2.
The fuel plunger or the air piston of
2.
Replace the fuel pump.
the fuel pump is leaking or seized.
Throttle Valve (Needle Block)
WARNING
Ensure the pressure has been relieved on the
remote throttle prior to disconnecting the remote
throttle hydraulic line.
The throttle valve (needle
1.
Possible air-lock in throttle needle of
1.
Remove the 1/8-inch NPT hex head pipe
block) does not operate
the throttle valve (needle block).
plug (bleed screw) on the side of the
properly.
throttle valve (needle block). Pressurize
the remote throttle to pump air out.
2.
The remote throttle and/or hydraulic
2.
Repair leaks in the hydraulic line and
line to the throttle valve (needle
associated fittings between the remote
block) is leaking hydraulic fluid.
throttle and throttle valve (needle block)
on the impact hammer. Tighten fittings
or replace lines as necessary.
3.
The throttle valve (needle block) is
3.
Replace the throttle valve (needle block).
defective.
Remote Throttle
The remote throttle does not
1.
The remote throttle and/or hydraulic
1a. Repair leaks in the hydraulic line and
function properly.
line to the throttle valve (needle
associated fittings between the remote
block) is leaking hydraulic fluid.
throttle and throttle valve (needle block)
on the impact hammer. Tighten fittings
or replace lines as necessary.
1b. Replace the remote throttle.
2.
The remote throttle does not build up
2a. Remove the small NPT end plug from the
pressure.
top of the remote throttle.
Close
pressure relief valve and set remote
throttle to pump, fill reservoir with MIL-
2105 fluid, and connect a compressed air
hose to reservoir filler. Pressurize with
compressed air to bleed system.
NOTE
Do not allow reservoir to empty.
2b. Replace the remote throttle.
The fuel injector(s) do not
1.
Defective fuel injector(s).
1.
Replace the fuel injector(s).
function properly.
CAUTION
Do not attempt to repair a fuel
injector in the field.
K-30 Change-1
