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Service
Fluid Packing Rod Removal and Repair
(continued)
8. Place the packing nut (28c) and o-ring (28g) on the
fluid rod (28b). The flats on the packing nut must
be facing toward the back of the fluid rod.
9. Fill the entire inner cavity of the spacer (28d) with
petroleum jelly. Place the spacer on the fluid rod
(28b), in the direction shown in Fig. 24. Generous-
ly apply petroleum jelly to the outside of the
spacer.
10. Place the fluid packing (28f), needle packing (28e),
and housing (28a) on the fluid rod (28b) as shown
in Fig. 24.
11. Lightly tighten the packing nut (28c). The packing
nut is properly tightened when there is 2 lbs. (9 N)
of drag force when sliding the packing housing
(28a) assembly along the shaft. Tighten or loosen
the packing nut as needed.
12. Lubricate the o-ring (28h) on the outside of the
packing housing (28a).
13. Install the fluid packing rod assembly (28) into the
gun barrel. Using the 9 mm hex nut driver (79),
tighten the assembly until it is just snug, then
check the drag on the fluid rod. See Fig. 23.
14. Make sure the spring (11) is installed on the nut
(U) as shown in Fig. 24.
15. Install the electrode needle, fluid nozzle and resis-
tor stud as instructed on page 31.
16. Install and adjust the actuator arm (19) and jam
nut (46) as instructed on page 34.
17. Test the gun resistance as instructed on page 27.
18. Install the gun shroud and air cap assembly.
19. Install the gun onto the manifold and bracket as
instructed on page 39.
Apply a very light coat of lubricant to the o-ring (28h).
Fill the inner spacer (28d) cavity with petroleum jelly and
generously lubricate the outside of the spacer.
Tighten the packing nut (28c) to 2 lbs (9 N) of drag force.
The spring (11) is not included with the fluid packing rod
assembly (28).
Fig. 24
28
28e
28a 28d
28b
28h
03224
28c
28f
28g
11
U
Piston Repair
1. Prepare the gun for service as instructed on
page 29.
2. Remove the air cap assembly and the gun shroud.
3. Remove the jam nut (46), actuator arm (19), and
adjustment nut (36). See Fig. 25.
NOTE: The fluid nozzle must be in place when remov-
ing or installing the jam nut and actuator arm.
03221
Fig. 25
46 19 36 23g
Continued on next page.