CRANE ROTATING FRAME BASE ASSEMBLY REPAIR INSTRUCTIONS
Section I. CRANE MAIN HOIST SHAFT ASSEMBLY
Crane Main Hoist Shaft Assembly Cleaning,
The crane main hoist shaft assembly is mounted on
the revolving frame between the horizontal swing shaft
Inspection, and Repair
and the jackshaft assemblies. It is secured to the frame
by two pillow blocks which are bolted to the frame and is
a. Cleaning. Clean all parts with an approved
chain driven from the jackshaft. The cable drums are
cleaning solvent and dry thoroughly.
held stationary by the brakes until the individual clutch
assembly is engaged, which in turn rotates the clutch
b. Inspection and Repair. Inspect all parts for
and brake drums. The main hoist shaft assembly can
excessive wear or damage. Replace or replace all
be removed as a unit without disturbing either horizontal
swing or jackshaft assemblies.
Crane Main Hoist Shaft Assembly Removal
Reassembly and Installation
a. Reassembly. Reassemble the crane main hoist
shaft assembly in the reverse of the numerical sequence
(1) Remove the main drum drive chain guard
(2) Remove the main drum and boom hoist
(1) Install the crane main hoist shaft
drive chains (TM 53810-20720).
(3) Remove the packing glands and
brakeband assemblies (TM 5-3810-207-
(3) Install the packing glands and brakeband
assemblies (TM 5-3810-20720).
(4) Remove the crane cab assembly (par.
(4) Install the main drum and boom hoist
drive chains (TM 5-3810-207-20).
(5) Remove the main hoist shaft assembly as
(5) Install the main drum drive chain guard
b. Dissemble. Disassemble the crane main hoist
shaft assembly in numerical sequence as illustrated on
Section II. JACKSHAFT ASSEMBLY
revolving frame as the hoist shaft. The jackshaft is the
means for transmitting power from the crane engine to
The jackshaft is located below and to the rear of the
main hoist shaft assembly and is secured by two pillow
blocks which are bolted to the same part of the