Figure 3-92. Boom hoist hydraulic brake cylinder, removal and installation.
Section XVIII. ROTATING BASE (REVOLVING FRAME)
3-117. General
counterweight extension installed.
The rotating base (revolving frame) of the crane-shovel
The unit could tip over backward,
unit is the mounting base for all operating components
causing damage to the unit, and
including front end attachments, engine, hoisting
possible injury to the operator.
mechanism, and cab. The revolving frame derives
swing power through a vertical swing shaft and revolves
3-118. Front Hook Rollers
on rollers traveling in the roller circle. Front and rear
a. Removal and Installation.
hook rollers are provided to reduce strain on center
(1) Lower boom to approximate horizontal
gudgeon, while 8,250 pounds of counterweight slugs in
position.
box plus the counterweight extension, provides stability
(2) Remove two capscrews, lockwashers, and
during swinging operation. Keep the hook rollers in
keeper plate from bracket (fig. 3-93).
proper adjustment at all times (para 3-35).
(3) Drive hook roller shaft backward slightly
to make lockring accessible, remove lockring, then pull
Warning: Never travel crane-shovel
hook roller shaft forward out of mounting bracket and
basic unit (less front end attachment)
remove hook roller.
over
rough
terrain
with
3-100
