RECOVERY VEHICLE, FULL TRACKED: MEDIUM, M88A1
HOISTING BOOM ASSEMBLY MAINTENANCE
DESCRIPTION, REMOVAL, DISASSEMBLY, INSPECTION, ASSEMBLY,
INSTALLATION, ADJUSTMENT, TESTING
Tools and Special Tools
The hoisting boom assembly is a tubular A-frame that is pivot-mounted to the top of the vehicle. Hydraulic pressure raises or
lowers the boom by means of two boom-actuating cylinders that are activated by the boom control lever. The hoisting boom
assembly is capable of holding a 25-ton (22.68-metric ton) load. In operating position, the boom is supported by a stayline cable
secured to crank arms located at the rear of the hull. These crank arms are connected to hydraulically actuated stayline cylinders
that govern the reaching capacity of the hoisting boom assembly. A boom travel lock is provided for preventing movement of
the boom, particularly sideways, while traveling.
Removal of hoisting boom assembly when both the main engine and APU engine are inoperable is a
safety hazard and may cause injury to personnel.
LOAD TEST REQUIREMENT--Load testing of hoisting boom assembly is mandatory, prior
to use, under any of the following requirements: (1) When new. (2) Following any repairs,
disassembly and assembly, adjustments, or parts replacement, of hoisting boom assembly. (3)
When modifications are made that could affect the strength or lifting capabilities of the vehicle.
Load testing will be accomplished by support maintenance activities.
Refer to the TESTING section below for the detailed step-by-step procedure.