TM 5-3810-295-34
b. Disassembly. Refer to figure 20-1 and disassemble
marks cannot be removed by light polishing.
f. Be sure that any paint or burrs raised on the body
the hydraulic pump as follows:
and cover mating surfaces are removed before asem-
(1) Mark cover (5), rotor ring (10) and body (19)
bly.
prior to disassembling. Note the direction of arrow cast
into rotor ring (10). The arrow indicates the direction of
20-5. Reassembly and Reinstallation
pump rotation.
a. Reassembly. Refer to figure 20-1 and reassemble
(2) Place the pump in a clamp vise with protective
the hydraulic pump as follows.
jaws, cover end up.
(1) Place shaft seal (18) in body (19) with the
(3) Remove pump gasket (3). Remove cap screws
spring facing towards bearing (17). Press seal ( S8) into
(4) and lift cover (5) off assembly.
body (19).
(4) Remove rotor ring assembly (10) from pump
(2) Supporting the inner race of bearing (17,
body (19).
press shaft (15) into the bearing. Install snap ring (14)
(5) Remove spring (6) and plate (7) from rotor ring
on the shaft.
(10). Remove and discard preformed packing (9).
(3) Using a soft headed hammer lightly tap the
(6) Carefully pull rotor (12) and vanes (11) out of
shaft and bearing assembly into body (19). Install snap
rotor ring (10). Remove vanes (11) from rotor (12). Note
ring (16) in the body to secure the shaft and bearing as-
the contour of rotor vanes to avoid error in reassembly.
sembly.
The contour faces out.
(4) If removed, install sleeve bearing (8) in press-
(7) Remove pin (13) from pump body (19).
ure plate'(7).
(8) Remove snap ring (16) from the body, and tap
(5) Place rotor (12) on pressure plate (7), and in-
shaft (15) and bearing (17) out.
sert vanes (11) in the rotor slots with radius edges
(9) If necessary, remove snap ring (14) and sup-
toward rotor ring (10).
porting inner race of bearing (17), press bearing off
(6) Install locating pins (13) in plate (7). Place,
shaft (15).
preformed packing (9) on rotor ring (10), and place the
(10)Remove shaft seal (18) from body (19).
ring over locating pins (13).
20-4. Cleaning, Inspection and Repair
NOTE
a. Clean all metallic parts of the pump with clean-
Rotor ring arrow must be pointed in the cor-
ing solvent (Fed. Spec. P-D-680, or equivalent) and dry
rect direction of rotation.
thoroughly with compressed air.
(7) Install spring (6) in cover (5). Use petroleum
b. Inspect wearing surfaces of rotor ring (10), and
jelly to hold spring in place if necessary-.
rotor (12) for scoring and excessive wear. Remove light
(8) Place preformed packing (9) on rotor ring (10)
scoring marks by lapping. Replace badly worn or
and assemble cover (5), rotor ring (10) and body (19)
heavily scored parts.
together. Secure with cap screws (4). Tighten cap
screws to 75-85 ft-lb (101.9--115.3 N ⋅m) torque.
c. Inspect the vanes for burrs, wear and excessive
play in the rotor slots. Carefully dress down burrs with
b. installation Refer to figure 20-1 and install the
a medium India stone. Replace the rotor if the slots are
hydraulic pump as follows.
worn. Replace vanes with a new vane kit if vane tips
(1) Place pump assembly on engine assembly,
are scored.
using gasket (3). Secure with lock washers (2) and cap
d. Rotate the bearing on the shaft while applying
screws (1).
presure to check for wear, looseness, roughness and
(2) Reconnect all hydraulic lines to the pump as-
pitted or cracked races.
sembly that were removed during the removal opera-
e. Inspect the seal and bushing mating surfaces on
tion.
the shaft for scoring or wear. Replace the shaft if
Section III. REPAIR OF UTILITY BLADE AND FAN
DRIVE DUAL HYDRAULIC PUMP
20-6. General
20-7. Maintenance
The utility blade and fan drive dual hydraulic pump is
Construction and maintenance procedures of the utility
mounted on the torque converter. One side of this dual
blade and fan drive dual hydraulic pump; 81"identical to
pump supplies hydraulic pressure for the utility blade and
the dual steering pump described in chapter 17, section
the steering control system. The other side supplies
IV.
hydraulic pressure to the fan motor.
20-3
