Blow the fluid passages of the valves
151. Outlet Selector Valve and
clear with compressed air.
Pressure Selector Valve
(2) Inspect the valves for cracks, breaks,
and damaged threads. Inspect the
(1) Disconnect the high pressure filter-to-
handles for free movement. Replace
outlet selector valve tubing (13, fig.
a defective or damaged valve.
12), outlet selector valve-to-reservoir
(3) Inspect all attaching hardware for
tubing (21), outlet selector valve-to-
distortion and damaged threads. Re-
outlet tubing (30 and 31).
place any defective hardware.
(2) Remove the bolt (31, fig. 9) that se-
cures the handle of the outlet selector
(1) Position the outlet selector valve (16,
valve (16) in place and remove the
fig. 9) in the control panel (1) and se-
cure in place with the four screws
(3) Remove the four screws (30) that se-
cure the valve to the control panel (1)
(2) Secure the handle of the outlet selector
and remove the valve.
valve in place with the bolt (31).
(4) Remove the pressure selector valve
(3) Connect the outlet selector valve-to-
(8) in a similar manner.
outlet tubing (30 and 31, fig. 12) out-
b. Cleaning and Inspection.
let selector valve-to-reservoir tubing
(1) Clean the valves with an approved
(21), and the high pressure filter-to-
cleaning solvent and dry thoroughly.
outlet selector valve tubing (13).
Section V. HYDRAULIC PUMP
a. Remove the control panel assembly (par.
The hydraulic pump is a variable volume,
axial piston-type unit designed to deliver up to
b. Drain and discard the hydraulic fluid from
10 gpm at a maximum 5000 psi. The volume
the pump by removing the plug in the pump
of fluid delivered is varied by changing the
length of piston strokes in the barrel. These
piston strokes are controlled by the angle of the
c. Disconnect the pump inlet-to-low pressure
cam plate against which they ride, The thrust
filter hose assembly (4, fig. 12) from the filter
of the pistons is balanced by the admission of
and manifold assembly (47) and pump (1).
pressure through a drilled hole in the piston
d. Disconnect the pump-to-manifold tubing
into an area in the surface of the piston shoe
(5) from the manifold and from the pump case
that contacts the cam plate. This area is slightly
relief valve in the pump. Remove the relief
valve from the pump.
less than the effective piston area, which results
from the shoe being supported on an oil film
e. Disconnect the pump-to-high pressure
at all times. The cylinder barrel is supported on
filter hose assembly (8) from the flared tube
tee (10) and from the check valve in the pump
a port plate into which are machined support
(1). Remove the check valve from the pump.
areas hydraulically balancing this portion of
the pump, The radial load created by the angle
f. Disconnect the pressure selector valve-to-
pump tubing (28) from the flared tube elbow
of the cam plate is supported by a roller bear-
(27) and pump (l).
ing. The cylinder barrel is driven by a spline
shaft. The variable delivery controls are bolted
g. Remove the roller chain (21, fig. 18) from
the two coupling halves (22 and 23).
to the pump housing in easily removable units.
All working parts are submerged in a bath of
h. Remove the four bolts (25) and lockwash-
ers (26) that secure the pump mount to the