Service
311051D
25
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 out-
let port of the fluid housing (2). See F
IG
. 22.
2.
All guns: Reinstall the gasket (22) in the fluid hous-
ing (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 bot-
tom of the piston housing (1), making sure the three
holes in the gasket are properly aligned with the
matching 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 F
IG
. 22. Place the gasket on the piston hous-
ing (1), then install the fluid housing (2) onto the pis-
ton housing. Torque the two screws (14) to 30 in-lb
(3.4 N•m).
a.
Insert the piston (3) into the piston housing (1).
b.
Ensure nozzle sealing o-ring (36) is installed in
fluid housing (2).
7.
To avoid galling of the fluid nozzle seat in the fluid
housing, apply a thin film of lubricant to the threads.
Install the nozzle into the fluid housing. Torque the
nozzle securely to 60 in-lb (6.8 N•m).
8.
Lubricate and install the needle (5) into the back of
the gun assembly. Push it straight in through the pis-
ton.
9.
Install the needle stop (29) on the needle. Coat the
setscrew (30) with semi-permanent anaerobic seal-
ant and install the screw into the needle stop.
Torque to 4-5 in-lb (0.45-0.56 N•m). Pull on the nee-
dle 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).
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.
