Graco A Series Instructions-Parts List Manual page 16

Displacement Pump Service
Disassembly
When disassembling the pump, lay out all removed
parts in sequence, to ease reassembly. Refer to Fig. 6.
NOTE: Repair Kit 218559 is available. For the best
results, use all the new parts in the kit. Parts included
in the kit are marked with one asterisk.
Always replace the glands when replacing the pack-
ings, whether or not you use a repair kit. Install the
packings one at a time to be sure they "nest" properly.
Clean all the parts thoroughly when disassembling.
Check them carefully for damage or wear, replacing
parts as needed.
1. Unscrew intake valve housing (6) from pump
housing (3). Remove pin (11), ball (9), retainer
(12), and o–ring (10). See Fig. 6. If seat in valve
housing (6) is chipped or worn, replace housing.
2. Loosen throat packing nut (4). Push displacement
rod (19) down until the piston body clears the
bottom of the pump housing (3). Grasp piston (5),
and pull piston and displacement rod out through
bottom of pump housing, being careful not to
scratch the sleeve inside the housing.
3. Screw the piston body (5) out of the rod (19).
Remove the ball (8), glands (31 and 32), packings
(14), shims (29) and packing retainer (21).
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.
4. Screw throat packing nut (4) out of pump housing
(3). Remove packings (14) and glands (31 and
32).
5. 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.
When replacing the sleeve, be sure to replace the
gasket (17*).
NOTE: If the sleeve (18) needs replacement and is
hard to remove, contact your Graco distributor.
306936
16
Service
Assembly
(215930 only)
1. Lubricate packings, displacement rod (19) and
2. Install male gland (31*), five v–packings (14*) with
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 up to six shims (29*) on the piston, to attain
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. Place ball (8*) on piston (5). Apply liquid thread
6. Place ball (9*) in intake housing (6) and install
7. Reconnect the displacement pump to the air motor
inside of sleeve (18) before assembling.
the lips facing down, and female gland (32*) in
throat of pump housing (3). See Detail A of Fig. 6.
Install packing nut (4) loosely.
the piston valve assembly into the displacement
rod (19) Torque to 35–40 ft–lb (47–54 NSm).
a packing stack height of 0.668–0.683 in.
(17.0–17.3 mm). Install the female gland (32*), five
v–packings (14*) with the lips facing up, male
gland (31*), and packing retainer (21) on the piston
(5). Verify that the packing stack height is correct.
See Detail B of Fig. 6.
sealant to threads of piston (5) and screw piston
into displacement rod (19). Torque to 35–40 ft–lb
(47–54 NSm). Install displacement rod (19) and
piston (5) up through bottom of pump housing (3).
o–ring (10), retainer (12), and pin (11) in housing.
Lubricate threads of valve housing (6) and screw
valve housing into pump housing (3). Tighten
throat packing nut (4) just enough to stop leakage
– no tighter.
as explained on page 13.