Graco Dura-Flo 900 Instructions-Parts List Manual page 22

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 215–327 N.m (159–241 ft-lb). See Fig.
8.
2. Place the piston packings on the piston seat
housing (16) in the following order, with the lips
of the v-packings facing up: See the Piston
Packing Stack Detail in Fig. 8.
a. the female gland (15*)
PTFE
b. one v-packing (14*)
c. four leather v-packings (12*)
d. the male gland (13*).
NOTE: If your pump uses an optional packing configu-
ration, or you want to convert the pump to a different
packing material, see pages 33 and 34.
3. Place the flats of the piston seat housing (16) in a
vise. Place the ball (11*) on the piston seat (E).
Screw the piston ball housing (10) onto the piston
seat housing hand tight, then torque to 215–327
N.m (159–241 ft-lb). See Fig. 7.
4. 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: See
the Throat Packing Stack Detail in Fig. 8.
a. the male gland (6*)
b. four leather v-packings (3*)
PTFE
c. one v-packing (5*)
d. the female gland (4*).
NOTE: If your pump uses an optional packing configu-
ration, or you want to convert the pump to a different
packing material, see pages 33 and 34.
Service (236466 Only)
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. 6. 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. 8), 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 289–389 N.m (213–287 ft-lb). This will
torque both cylinder joints (A and B). See Fig. 6.
12. Using a pipe wrench, torque the intake valve (19)
to 176–230 N.m (130–170 ft-lb). See Fig. 6.
13. Torque the packing nut (2) to 128–156 N.m
(95–115 ft-lb).
14. Reconnect the displacement pump to the air motor
as explained on page 18.