Graco 25T991, Instructions - Parts Manual

Page: 18 / 52

Repair
18 3A8476A
Remove the Pneumatic Section
1. Air cylinder assembly (401-417) and needle ball
shut off valves (418) are removed together by
removing the three M5 SHCS screws (408).
NOTE: Be careful to not damage or bend the needle ball
shut off valves (418) when extracting from housing.
Various seals and gaskets that are discarded in the
following procedures need to be replaced by new before
reassembly.
2. Air gaskets (410) should be discarded.
3. Remove air manifold (516) by removing M3 SHCS
screw fasteners (517) with a hex key wrench. Air
gasket (514) should be discarded.
4. Remove inner cover (513) by removing M3 flathead
screws (515)with a hex key wrench.
5. Remove the 1/8 in. BSPP swivel elbow fitting (512)
with a hex key wrench. See F
IG
. 15.
Remove Pneumatic Section
1. Detach cylinder cover (402) by removing three M4
SHCS screws (401) with hex key wrench. Loosen
screws evenly because the cover is under spring
(403) tension and could bind when removed.
2. Loosen M3 set screws (405) three turns each and
pull ball shut off needles (418) out of the assembly.
See F
IG
. 16.
3. Extract pistons (404) from air cylinder housing (409)
Discard guide rings (406) and O-rings (407).
4. Remove short and long seal bearing guides (413
and 414) with a 10mm wrench.
5. Using a knife edge tool or screwdriver, carefully pry
the lower bearings (417) out of the seal bearing
guides (413-414). Discard lower bearings.
6. Using a hook tool extract the needle packing (411)
seals from the seal bearing guide side and discard.
7. Remove the two needle packing (411) seals and
upper bearings (412) from the seal bearing guides
and discard the needle packing and upper bearings.
8. Remove the O-rings (415 and 416) and discard.
See F
IG
. 17.
F
IG
. 15
408
517
401-417
410
516
512
514
513
515
F
IG
. 16
F
IG
. 17
403
401
418
402
409
405
404
407
406
409
415
411
411
413
414
412
411
416
417