Graco 247937, 247936 important safety instructions Repair Packing Rod

Gun Repair

Repair Packing Rod

You may replace the packing rod as individual parts or as an assembly. The assembly is pre-adjusted at the factory for proper air lead and lag. The gun begins emit- ting air before the fluid is discharged and the fluid stops before the air flow stops.

To adjust the lead/lag air flow:

1.Remove the spring (4) from the nut (E).

2.Use a hex wrench to hold the end of the packing rod. Turn the nut (E) out to increase the lead/lag time for the air flow. The recommended adjustment is one half turn and not more than one full turn.

3.Apply thread-locking adhesive to fix the nut in the new position.

Before installing the fluid packing rod into the gun barrel, make sure the internal surfaces of the barrel are clean. Remove any residue with a soft brush or cloth. Check the inside of the barrel for marks from high voltage arcing. If marks are present, replace the barrel.

To assemble the individual parts:

1.Place the packing nut (26g) and seal (26f†) on the fluid rod (26a). Flats on the packing nut must face the back of the fluid rod. The seal o-ring must face away from the packing nut. See FIG. 15.

2.Fill the inner cavity of the spacer (26e†) with dielec- tric grease (40). Place the spacer on the fluid rod (26a) in the direction shown. Generously apply dielectric grease to the outside of the spacer.

3.Place the rod packing (26d†), packing spreader (26c†), and housing (26b) on the packing rod (26h).

4.Lightly tighten the packing nut (26g). The packing nut is properly tightened when there is 3 lb (13.3 N) of drag force when sliding the packing housing (26b) assembly along the rod. Tighten or loosen the pack- ing nut as needed.

5.Install the o-ring (26h†) on the outside of housing (26f). Lubricate the o-ring with non-silicone grease, Part No. 111265. Do not over-lubricate.

6.Install the spring (4) against the nut (E) as shown.

7.Install the packing rod assembly (26) into the gun barrel. Using the multi-tool (37), tighten the assem- bly until just snug.

8.Install the trigger (30) and screws (8).

9.Install the fluid needle page 28.

10.Install the nozzle and air cap, page 28.

11.Install the probe.

4

E

26a

26d†

26c†

26b

26h†

26g

26f†

26e†

ti12719

Fig. 15. Packing Rod

30 312900G