Graco A Series Instructions-Parts List Manual page 24

Reassembling the pump
NOTE: Alternate plastic and leather packings. See Fig.
21. The lips of the throat V-packings face down,
against pressure. The lips of the piston V-packings
face up, against pressure. The lips of the u–cup face
down. Incorrect installation damages the packings and
causes pump leaking.
NOTE: Soak the leather packings in oil before reas-
sembling the pump.
1. Check the outside of the piston rod (107) and the
inside of the cylinder (115) for wear. Replace worn
parts to ensure a good seal with the new packings.
2. Stack these parts onto the piston valve (108) one
at a time: the backup washer (126*) and u–cup
(125*), female gland (114*), alternately three
plastic (112*) with two leather packings (113*),
and the male gland (111*). See Fig. 22.
3. Tighten the nut (110) onto the piston valve (108) to
0.23 N.m. See Fig. 22.
NOTE: Note the alignment of the piston (108) to the
nut (110). Maintain this alignment through Step 8.
4. Clean all residue from the piston valve threads.
Apply one strip of adhesive, supplied, to the
threads.
5. Place the ball (109*) on the piston valve (108). See
Fig. 22.
CAUTION
Step 6, tightening the piston valve into the rod, is
critical. Follow the procedure carefully to avoid
damaging the packings by overtightening.
6. Hand tighten the valve into the piston rod just until
the nut (110) contacts the rod. See Fig. 23.
Displacement Pump
7. Place the flats at the top of the rod in a vise.
8. Carefully tighten the nut (110) against the piston
rod to 40 N.m. See Fig. 23.
Use two wrenches to maintain the alignment
mentioned in the NOTE, at left.
A
Torque to 0.57 N.m
Apply one drop of
B
sealant to these
threads
110
A
*111
*113
*125
*126
Fig. 22
Torque nut against
A
rod to 40 N.m
Do not allow nut (110) to
B
move relative to piston
(108) when tightening piston
against rod
110
A B
Fig. 23
9. Stack these parts one at a time into the top of the
manifold (101): the male gland (106*), alternately
three plastic packings (104*) with two leather
packings (105*), and then the female gland (103*).
See Fig. 24.
10. Install the packing nut (102) and plug (124), but
leave loose for now. See Fig. 24.
11. Place a new o–ring (116*) firmly in the cylinder
groove. See Fig. 25.
107
109*
B
112*
114*
108
03178
107
108
B
03179