Graco Series D, Instructions And Parts List

Page: 16 / 24

Repair
16 308608L
19. Clamp the flats of the piston/valve seat (109) in a
vise, and torque the piston rod (29) to the piston
valve seat to 40 to 60 ft.-lbs (54 to 81 N•m).
20. Clamp the air motor base (28) in a vise horizontally
by closing the vise jaws on the flange.
21. Use a strap wrench to screw the displacement
pump cylinder (110) to the air motor base (28), and
torque to 95 to 105 ft.-lbs (129 to 142 N•m).
22. Before remounting the pump, connect an air hose
and run the air motor slowly, starting with just
enough air pressure to make the air motor run, to
make sure that it operates smoothly.
23. Reconnect the ground wire before regular
operation of the pump.
Displacement Pump
Disassembly
Displacement Pump Repair Kit 238225 includes repair
parts for the pump throat and piston. For best results,
use all of the parts in the kit. Parts included in the kit are
marked with a dagger, for example (7†), in the text and
drawings. See Parts List , page 17.
1. Flush the pump.
2. Relieve pressure. Follow the Pressure Relief
Procedure , page 8.
3. Disconnect the hoses, remove the pump from its
mounting, and clamp the air motor base (28) in a
vise horizontally by closing the vise jaws on the
flange.
Intake Valve
Refer to F
IG
. 5 for the following instructions.
1. Relieve pressure. Follow the Pressure Relief
Procedure , page 8.
2. Unscrew the valve housing (111). Remove the
o-ring (105†), retainer (112), and ball (104).
3. Inspect the parts for wear or damage. If the ball is
nicked, replace it. Reassemble, using grease on the
male threads.
Displacement Pump
Refer to F
IG
. 5 for the following instructions.
Clean and inspect all parts for wear or damage during
disassembly. Replace parts as needed. For best
results, always replace all of the o-rings and packings
during disassembly of the pump.
1. Relieve pressure. Follow the Pressure Relief
Procedure , page 8.
2. Follow steps 1 to 7 of Air Motor and Throat
Disassembly , page 12.
3. Carefully inspect the smooth inner surface of the
cylinder (110) for scoring or irregular surfaces. Such
damage causes premature seal wear and leaking.
Replace the cylinder as needed.
Reassembly
Follow steps 16 through 23 of Air Motor and Throat
Reassembly , page 15.
†Included in Pump Repair Kit 238225, which may be
purchased separately.
F
IG
. 5