TM 5-5420-280-10
0037 00
Pallet Hydraulic Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
7. LAUNCH BOOM WILL NOT LOWER OR RAISE (L6-A, L12-A, L15-A, L20-H, or R4-
A+H+M, R11-A, R9-A, and R16-A)
Step 1. Check if launch boom lock retaining pins are installed.
Remove launch boom lock retaining pins. Refer to WP 0007 00.
Step 2. Check for damaged hydraulic tubing.
If hydraulic tubing is damaged, notify field maintenance.
Step 3. Check for damaged or missing launch boom lock pins and retaining
bracket on launch boom and main shaft pallet frame.
a. If launch boom lock pins and retaining bracket on launch boom
and main shaft are damaged or missing, notify field maintenance.
b. If four hydraulic fittings on main shaft are damaged due to
missing pin, notify field maintenance.
Step 4. Check for malfunctioning control valve.
If control valve does not function, notify field maintenance.
END OF TESTING
8. LAUNCH BOOM WILL NOT LOWER TO COUPLING POSITION (L14-A or R2-H)
Check for malfunctioning control valve.
If control valve does not function, notify field maintenance.
END OF TESTING
9. LOWER SUPPORT BOOM CYLINDERS WILL NOT EXTEND OR RETRACT (L14-A or R2-H)
Step 1. Check for malfunctioning control valve.
If control valve does not function, notify field maintenance.
Step 2. Check for malfunctioning pressure switches KF-1 and KF-2. Notify
field maintenance to test switches.
Step 3. Check hydraulic hoses, tubing, and cylinders for damage or missing
pins.
a. If hydraulic hoses or steel tubing are damaged, notify field
maintenance.
b. If hydraulic cylinder(s) or pins are damaged or missing, notify field
maintenance.
END OF TESTING