Graco Inc 308741N dimensions 20 or 25b 19 or 25a

Service

11.Place the new fluid packings (5) and packing screw (8) onto the needle (13). See Fig. 27, page 19, for the orientation of the parts.

12.Insert the fluid needle (13) into the back of the insert (4) to install the fluid packings (5).

13.Tighten the packing screw (8) just enough to hold the packings (5) in the insert (4). The needle (13) must move freely. Remove the needle.

14.Unscrew the pattern adjustment valve assembly (25).

15.Remove the retaining ring (25d) and unscrew the pattern adjustment valve (25c).

16.Remove the u-cup seals (25b) from the pattern adjustment nut (25a). Be careful not to damage the seal surface or the nut’s internal threads.

17.One at a time, install the new u-cup seals (25b) with the seal installation tool (29); the u-cup lips must face toward the tool as shown in Fig. 31.

18.Push each u-cup seal (25b) into the pattern adjust- ment nut (25a) until a definite snap is felt.

19.Lubricate the pattern adjustment valve (25c) threads and install the valve into the nut (25a). Install the retaining ring (25d), then back out the pattern adjustment valve as far as the retaining ring allows it to go.

20.Remove the fluid valve nut (19), air valve spring (22), and air valve assembly (26). Discard the air valve assembly. See Fig. 28, page 19.

21.Remove the u-cup (16) from the gun body. The threaded end of the needle (13) can be used to push out the u-cup. Be careful not to damage needle or sealing surface. See Fig. 29.

22.Place the new u-cup (16) on the seal installation tool (29), with the u-cup lips facing the tool as shown in Fig. 30.

23.Push the packing (16) into the back of the gun until a definite snap is felt.

24.Remove the u-cup seal (20) from the fluid valve nut (19). Be careful not to damage the seal surface or the nut’s internal threads.

25.Install the new u-cup seal (20) with the seal instal- lation tool (29); the u-cup lips must face toward the tool as shown in Fig. 31. This will help apply even pressure to the u-cup lips and avoid damaging them.

26.Push the u-cup seal (20) into the fluid valve nut

(19)until a definite snap is felt.

13

Fig. 29

1 U-cup lips face the tool

161

29

Fig. 30

1	U-cup lips face	29
	the tool

20 or 25b 1

19 or 25a

Fig. 31

308741 21