Reassembly

1.Non-circulating guns only: Lubricate the backup ring (20†) and o-ring (21†) and install them on the fluid outlet port plug

(19). Install the plug in the fluid outlet port of the fluid housing (2). See FIG. 20.

2.All guns: Reinstall the gasket (22) in the fluid housing (2).

3.Install the o-rings (8*, 9*) on the piston (3). Install the two o-rings (10*, 11*) on each of the piston stems (T). Lubricate all the o-rings, the piston, and the piston stems.

4.Remove the protective paper from the sticky side of the gasket (12*) and adhere the gasket to the bottom of the piston hous- ing (1), making sure the three holes in the gasket are properly aligned with the match- ing holes in the housing.

5.Lubricate the new fluid packing (17†) and insert it into the packing nut (16). Insert the packing nut into the fluid housing (2) and torque to 95-105 in-lb (10.7-11.8 N•m).

6.Align the gasket (15*) as shown in the exploded view in FIG. 20. Place the gasket on the piston housing (1), then install the fluid housing (2) onto the piston housing. Torque the two screws (14) to 35-45 in-lb (4.0-5.1 N•m).

a.Insert the piston (3) into the piston housing (1).

b.Ensure nozzle sealing o-ring (36) is installed on nozzle (23).

7.To avoid galling of the fluid nozzle seat in the fluid housing, apply a thin film of lubri- cant to the threads. Install the nozzle into the fluid housing. Torque the nozzle securely to 35-45 in-lb (4.0-5.1 N•m).

Service

NOTE: If you are replacing the needle tip (5a), apply semi-permanent anaerobic sealant to two threads at the end of the needle shaft. Assemble the needle tip to the shaft and hand tighten. Allow adequate time for the sealant to cure before installing the needle assembly into the gun.

8.Lubricate and install the needle (5) into the back of the gun assembly. Push it straight in through the piston.

9.Install the needle stop (29) on the needle. Coat the setscrew (30) with semi-perma- nent anaerobic sealant and install the screw into the needle stop. Torque to 4-5 in-lb (0.45-0.57 N•m). Pull on the needle to make sure it seats fully.

10.Install the springs (6, 7).

11.Lubricate the threads of the piston housing

(1). Screw the cap (4) onto the housing until it bottoms out.

12.Install the air cap (24) and air cap retainer (25).

13.Reinstall the gun on the manifold using the four screws (13). Start the threads of all four screws. Tighten the front two screws first, and then tighten the back two. Torque all four screws evenly to 65 in-lb (7.3 N•m).

313516C

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Graco Inc 313516C important safety instructions Reassembly