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308354
Service
Reassembly
1.
If it was necessary to remove the piston ball
housing (10) from the displacement rod (1), clean
the threads of the rod and the ball housing. Screw
the ball housing onto the rod, hand tight. Place the
flats of the piston ball housing in a vise and torque
the rod to 271–298 N.m (200–220 ft-lb). See Fig.
9.
2.
For standard displacement pump 236470, place
the piston packings on the piston seat housing (16)
in the following order, with the lips of the v-pack-
ings facing up: the female gland (15*), one PTFE
v-packing (14*), four leather
v-packings (12*), and the male gland (13*).
See the Piston Packing Stack Detail in Fig. 9.
NOTE: If your pump uses an optional packing configu-
ration, or you want to convert the pump to a different
packing material, see page 27.
3.
Place the flats of the piston seat housing (16) in a
vise. Place the ball (11*) on the housing. Screw the
piston ball housing (10) onto the piston seat hous-
ing hand tight, then torque to 271–298 N.m
(200–220 ft-lb). See Fig. 8.
4.
For standard displacement pump 236470, lubricate
the throat packings and place them in the outlet
housing (7) in the following order, with the lips of
the v-packings facing down: the male gland (6*),
four leather v-packings (3*), one
PTFE v-packing (5*), and the female gland (4*).
See the Throat Packing Stack Detail in Fig. 9.
NOTE: If your pump uses an optional packing configu-
ration, or you want to convert the pump to a different
packing material, see page 27.
5.
Install the packing nut (2) loosely into the outlet
housing (7).
6.
Lubricate the piston packings. Slide the displace-
ment rod (1) and piston assembly down into the
cylinder (9). The cylinder is symmetrical, so either
end may face up. Use a rubber mallet to drive the
rod into the cylinder, until the piston seat housing
(16) is near the bottom of the cylinder.
7.
Install the seal (8*) on the top of the cylinder (9).
Lubricate the seal and the top threads of the
cylinder.
8.
Place the outlet housing (7) in a vise, as shown in
Fig. 7. Slide the displacement rod (1) up into the
outlet housing, then screw the cylinder (9) into the
outlet housing handtight. The threads will engage
easily until the seal (8*) contacts the sealing
surface of the outlet housing. The top of the rod
will protrude from the packing nut (2).
9.
Install the seal (8*) on the bottom of the cylinder
(9). Lubricate the seal and the threads of the
cylinder. With the beveled ball stop surfaces (S)
facing down (see Fig. 9), screw the intake hous-
ing (18) onto the cylinder handtight. The threads
will engage easily until the seal contacts the seal-
ing surface of the intake housing.
10. Install the seal (8*) on the intake valve (19). Lubri-
cate the seal and the threads of the intake valve.
Place the intake ball (17*) in the intake housing
(18), then screw the intake valve into the intake
housing handtight. The threads will engage easily
until the seal contacts the sealing surface of the
intake housing.
11. Using a pipe wrench, torque the intake housing
(18) to 325–353 N.m (240–260 ft-lb). This will
torque both cylinder joints (A and B). See Fig. 7.
12. Using a pipe wrench, torque the intake valve (19)
to 190–217 N.m (140–150 ft-lb). See Fig. 7.
13. Torque the packing nut (2) to 136–149 N.m
(100–110 ft-lb).
14. Reconnect the displacement pump to the air motor
as explained on page 16.