TM 5-3820-241-34
CHAPTER 3
MAINTENANCE OF THE HYDRAULIC SYSTEM
Section I. HYDRAULIC CYLINDERS
3-1. General
The pneumatic rock drill is equipped with five
hydraulic cylinders, one each for feed lift, boom
lift, feed swing, boom swing, and feed extension.
All hydraulic cylinders are double acting and self-
locking when not in operation. Additional
protection is provided by pilot check valves that
prevent cylinder movement, except when in-
tended or in the event of line breakage.
3 - 2 . F e e d T i l t C y l i n d e r R e m o v a l a n d
Disassembly
a. Removal.
(1) Lower the rock drill feed mechanism to
rest on the ground.
(2) Loosen hose connections and allow
hydraulic oil to bleed into a container.
(3) Remove
the
feed
tilt
cylinder
in
numerical sequence as illustrated in figure 3-1.
3-1
