Repair; Pump - Graco 24T918 Instruction Manual

Repair

Repair
NOTE: Some procedures require special tools. Read
through each procedure prior to beginning it to ensure
you have the required tools to complete the entire pro-
cedure. Order any required tools and have them on
hand prior to beginning the procedure.
When performing any procedure that requires
removal of seals or other soft parts, do not leave a
system that has not been flushed disassembled for
more than 30 minutes to prevent the adhesive from
hardening. Hardened adhesive will damage the seals
and other soft parts during installation.

Pump

Replace Throat Seal, Throat Bearing, Piston Rod,
Piston Seal, and Piston Bearing
218
240
27
223
226
245
3
F . 31
IG
56
NOTICE
239
235
233
234
238
222
224
225
Disassembly (see F . 31):
IG
1. Flush the system. See page 34.
2. Close the bleed-type ball valve installed at the sys-
tem air inlet to relieve all air pressure in the system.
3. Turn main power switch OFF.
4. Remove plastic shroud (27).
5. Remove vacuum transfer inlet funnel.
6. Remove air lines from relief valve (245) and air
motor (218).
7. Remove four nuts (3) securing melter shield (27) in
place then remove melter shield.
8. Remove air motor assembly:
a. Remove retaining ring (239).
b. Remove dowel pin (238).
c. Remove three screws (240).
9. Use a flat head screwdriver and a rubber mallet to
break loose the retaining nut (235).
10. Use channel lock pliers to remove the retaining
nut (235).
11. Insert an allen wrench through the hole in the top of
the piston rod (223) to lift the piston rod (223) up out
of the manifold. This will also pull out the throat
u-cup (234) and throat bearing (233).
12. Remove piston valve (222) from piston rod (223).
13. Remove and discard piston u-cup (225) and
bearing (226).
Reassembly (see F . 31):
IG
1. Assemble piston rod:
a. Install new piston u-cup (225) onto piston
rod (223) with the lips facing the rod.
b. Install piston bearing (226) onto piston rod (223)
with grooved end towards the center of the pis-
ton rod.
333347F