Reassembly Procedure; Reassembly Notes - Graco GM 5000 Instructions And Parts List

Displacement Pump Repair
4. To disassemble the rest of the pump, remove the
packing nut (416) and plug (405). See Fig. 33.
5. Use a plastic mallet to tap the piston rod (424) down.
Pull the rod out through the bottom of the cylinder.
6. Remove the throat packings. See Fig. 33.
WARNING
Always use the special sleeve removal tool, P/N
220–991, to remove the sleeve. Other removal meth-
ods could cause the pump to rupture, resulting in seri-
ous injury. If the sleeve cannot be removed easily us-
ing the tool, return the sleeve and cylinder to your
Graco distributor for removal.
7. Remove the sleeve. Screw the large nut (B) of the
tool into the top of the cylinder (419). Screw down the
rod (A) to push the sleeve out. Remove the tool. See
Fig. 29.
8. Clamp the flats of the piston rod (424) in a vise. Loos-
en the retaining nut (411). Unscrew the piston valve
(422). See Fig. 30.
9. Disassemble the piston valve (422). See Fig. 30.
Fig. 29

Reassembly Notes

1. Pump Repair Kit, P/N 220–877, is available. For the
best results, use all the new parts in the kit, even if
the old ones still look good. Parts included in the kit
are shown with an asterisk, e.g., (410*) in the text
and drawings.
2. Check the outside of the piston rod (424) and the in-
side of the sleeve (418) for scoring or scratches. If
the parts are damaged, new packings will not seal
properly. Replace these parts if needed.
A
B
419
0028
3. Alternate leather and plastic packings as shown in
Fig. 30. The lips of the throat "V" packings must face
down. The lips of the piston "V" packings must face
up. The lips of the U–cup seal (403) face down. Incor-
rect installation damages the packings and causes
the pump to leak.
4. Soak leather packings in oil before reassembling the
pump.

Reassembly Procedure

1. Stack the backup washer (414), seal (403*), female
gland (415*), alternate the packings (412*,406*), and
then male gland (410*) onto the piston valve (422).
See Fig. 30.
2. Tighten the packing retaining nut (411) onto the pis-
ton valve (22) to the torque specified in Fig. 30.
3. Put the ball (425*) on the piston valve (422). See
Fig. 30.
CAUTION
Step 5, tightening the piston valve into the rod, is criti-
cal. Follow the procedure carefully to avoid damaging
the packings by overtightening.
4. Apply one drop of adhesive, supplied, to the threads
of the piston valve. Then hand tighten the valve as-
sembly into the piston rod just until the nut (411) con-
tacts the rod. See Fig. 30.
NOTE: Note the alignment of the piston (422) to the nut
(411). Maintain this alignment through Steps 5, 6 and 7.
5. Place the flats at the top of the rod (424) in a vise.
Torque to
4 in-lb (0.35 N.m)
Apply one drop
of sealant to
these threads
Lips face up
Lips face down
411
*406
*412
414
Fig. 30
424
425*
410*
415*
403*
422
0029