TM 5-3820-239-15
(9) Install rotor (8) on drive shaft (16)
the flanged face of motor housing
and insert vanes (9) in the rotor
(19) with a mallet, to seat the parts
slots with the rounded edges facing
and eliminate binding.
outward.
Note . Make sure motor pinion (14) can
(10) Stand the pump on its shaft end, and
be rotated freely when housing cover (4)
position pressure plate (4) on ring
is installed.
(7). Insert spring (3) into the center
b. Hydraulic Pump. Reassemble hydraulic
recess hole of the pressure plate.
pump by carefully following the step-by-step
(11) Install cover (2) in the proper posi-
procedure given below:
tion as marked during disassembly,
(1) Before assembling, dip all parts in
and tighten screws (1) to a torque of
clean hydraulic oil. This will facilitate
22 to 28 feet-pound.
assembly, and provide adequate ini-
Note. Check that the pump turns freely
tial lubrication.
by hand. If the pump binds, disassem-
(2) Using a suitable bearing pusher to
ble and determine the cause of trouble.
bear on the inner race of bearing (11,
c. Hydraulic Pump Assembly . Reassemble
hydraulic pump assembly in reverse of numeri-
drive shaft (16).
cal sequence as illustrated on figure 6-9. Note
(3) Using a suitable bearing pusher to
the following special procedures:
bear on the outer race of bearing
(1) A f t e r s e c u r i n g a i r m o t o r ( 1 8 ,
(13), install the bearing in body
(17).
ing (19), loosen setscrews on flexible
(4) Install spacer (15), seal (14), and
coupling (14). Make sure that square
key (12) on drive shaft (16).
key (15) is installed in slot of air
Note . Make sure the seal is installed
motor shaft, and slide the flexible
with the sealing lip facing the key end
coupling onto the shaft. Tighten the
of the shaft, to prevent the entry of air
setscrew.
into the system.
(2) M a k e s u r e t h a t k e y o f h y d r a u l i c
(5) Slide the assembled drive shaft (16)
pump (13) is installed on the shaft
into body (17) until seated in bearing
and insert the pump so that the key
(13). Tap the drive shaft lightly with
enters the keyway of flexible cou-
a mallet if necessary, to seat the parts.
pling (14). Install screws (10), nuts
(6) Using retaining ring pliers, install
(ll), and lock washers (12), and
snap ring (10).
tighten the setscrew (1) of the flexi-
ble coupling.
(7) Insert an O-ring (6) in the groove of
(3) Install elbows and fittings as shown
body (17) and cover (2). Make sure
on figure 6-9.
the O-rings are seated properly to
prevent leakage.
6-21. Installation
(8) Install ring (7) in the proper position
as marked during disassembly, and
Install the hydraulic pump assembly as de-
secure with pins (5).
scribed in paragraph 3-44.
Section IV. HYDRAULIC VALVE ASSEMBLY
6-22. General
6-23. Removal
Remove the hydraulic valve assembly as de-
This section contains repair instructions for
scribed in paragraph 3-58.
the hydraulic valve assembly. The hydraulic
valve assembly contains the controls for oper - 6-24. Disassembly
ating the hydraulic cylinders to position the
a. Hydraulic Valve Assembly . Disassemble
boom and the drill guide (fig. 1-5).
hydraulic valve assembly in the numeri-
