Graco A Series Instructions-Parts List Manual page 14

Displacement Pump Service
Disassembly
When disassembling the pump, lay out all removed
parts in sequence, to ease reassembly. Refer to Fig. 5.
NOTE: Repair Kit 235634 is available. For the best
results, use all the new parts in the kit. Parts included
in the kit are marked with one asterisk, for example
(8*).
Conversion Kit 220396 is available to convert the
pump packings to UHMWPE and leather. See page 19
for details.
Clean all the parts thoroughly when disassembling.
Check them carefully for damage or wear, replacing
parts as needed.
1. Remove the displacement pump from the air motor
as explained on page 13. Place the displacement
pump in a vise.
2. Unscrew the intake valve body (6) from the pump
housing (3). Remove the ball stop pin (11), retainer
(12), o-ring (10), and ball (9). See Fig. 5.
3. Loosen the packing nut (4). Push the displacement
rod (19) down until the piston body (5) clears the
bottom of the pump housing (3). Grasp the piston
and pull the rod straight out, being careful not to
scratch the sleeve (18) inside the housing.
4. Screw the piston body (5) out of the rod (19).
Remove the ball (8), packing retainer (21), glands
(16, 13), and packings (14, 15).
NOTE: Inspect the ball stop pin (20) and ball guide
(36) in place. If either is damaged, or if the displace-
ment rod is being replaced, remove one cotter pin (7)
and pull the ball stop pin out of the rod (19). Remove
the ball guide.
5. Remove the packing nut (4) from the pump hous-
ing (3). Remove the throat glands (13, 16) and
packings (14, 15).
6. Clean all parts and threads with a compatible
solvent and blow dry before reassembling. Inspect
all parts for wear or damage. Inspect the polished
surfaces of the displacement rod (19) and sleeve
(18) for scratches, scoring or other damage, which
can cause premature packing wear and leaking. To
check, run a finger over the surface or hold the
part up to the light at an angle. If one of these
parts is worn or damaged, replace both parts.
306936
14
Service
NOTE: If the sleeve (18) needs replacement and is
(217529 Only)
hard to remove, contact your Graco distributor.
Reassembly
1. Lubricate the packings, glands, displacement rod,
2. Install the piston packings onto the piston body (5)
NOTE: If the ball stop pin (20) and ball guide (36) were
removed from the displacement rod during disassem-
bly, reinstall them and secure with the cotter pins (7).
Make sure the ball stop pin is in the top set of holes.
3. Install the piston ball (8*) on the piston and screw
4. Install the throat packings in the pump housing (3)
NOTE: If you removed the sleeve (18), reinstall it in
the outlet housing (3), making sure to replace the
gasket (17*). Be sure the tapered end of the sleeve
faces down, toward the pump intake.
5. Insert the displacement rod (19) into the bottom of
6. Install the ball (9*), o-ring (10), retainer (12), and
7. Reconnect the displacement pump to the air motor
and sleeve with a compatible grease before reas-
sembling the pump.
one at a time in the following order, with the lips of
the v-packings facing up: the female gland (13*),
two PTFE v-packings (14*), one leather v-packing
(15*), one PTFE (14*), one leather (15*), the male
gland (16*), and the packing retainer (21). See
Detail B of Fig. 5.
the piston valve assembly into the displacement
rod (19). Torque to 35–40 ft–lb (47–54 NSm).
one at a time as follows, with the lips of the v-
packings facing down: the male gland (16*), one
leather v-packing (15*), one PTFE v-packing (14*),
one leather (15*), two PTFE (14*), and the female
gland (13*). See Detail A of Fig. 5.
the pump housing (3). Push the rod straight up,
being careful not to scratch the sleeve (18) or
damage the throat packings. Install the packing nut
(4) loosely.
ball stop pin (11) in the intake valve body (6).
Screw this assembly into the pump housing (3).
Torque to 55–65 ft–lb (75–88 NSm).
as explained on page 13.