HP 288048 - Manual (Page 17)

Service
311053C 17
Service
Disassembly
1. Follow Pressure Relief Procedure, page 11.
2. Unscrew the four screws (14) and remove the gun
from the manifold.
3. Unscrew the tip retainer nut (7). Remove the spray
tip (9) and gasket (8). See Figs. 8 and 9.
4. Remove the cap (18) from the piston housing (1).
Remove the springs (20 and 19).
5. Using the supplied wrench (34), loosen the fluid
needle setscrew (16). Remove the needle stop (17).
6. Remove the seat (10, 41).
7. Pull the needle assembly (12) straight out the front
of the gun. Remove the o-rings (31) from the fluid
needle (12).
8. Remove the gasket (11).
9. Remove the piston. Using a pliers, pull the piston
(21) out of the piston housing (1).
10. If necessary, unscrew the two screws (15) holding
the fluid housing (2) to the piston housing (1). If
worn, remove the gasket (13) from the bottom of the
piston housing.
11. Remove the large o-ring (22) from the piston and
the smaller o-ring (23) from the piston shaft.
Remove the two o-rings (25, 26) from each of the
piston stems. Check that the stems are solidly in
place. If they are loose, replace the entire piston
assembly (21).
12. Perform the following applicable step:
• Non-circulating Paint Guns: Remove the fluid
outlet port plug (4) and gasket (3) from the fluid
housing (2). Remove the o-ring (5) and backup
(6) from the plug.
• Circulating Paint Guns: Remove the gasket (3)
from the fluid housing (2).
• Sealant Gun: Remove the gasket (3).
13. Clean all parts and replace any worn parts. When
assembling, lubricate the threads with anti-seize
lubricant.
Follow the Service Notes in Figs. 8 and 9 when
reassembling the gun.
Gun repair kits are available. See page 18. Refer-
ence numbers marked with an asterisk (*) in the
service procedures are included with the 288171
Air Seal Repair Kit. Reference numbers marked
with a symbol (†) in the service procedures are
included with the 288137 Fluid Repair Kit.
CAUTION
Be sure to keep the needle straight when removing it
from the gun. If the needle is bent it must be replaced.
CAUTION
Install a new gasket (11) whenever you remove the
seat (10, 41) from the gun. Failure to install a new
gasket may result in fluid leaking into the air chamber.
F IG . 12
1
15
2
15
TI8197a
38
(model 288554 only)