Graco 231-353 Instructions-Parts List Manual page 23

Displacement Pump Repair
Intake valve repair
(See Fig. 17)
1. Remove the suction hose. See Step 2, Removing
the pump.
2. Unscrew the intake valve (118). Remove the
o-ring (119*), ball guide (120), stop pin (122*) and
ball (121*) from the valve.
3. Clean and inspect the parts for wear or damage.
Replace parts as needed. Use a new o–ring
(119*). If no further service is needed, reassemble
the pump.
Disassembling the pump
1. Remove the intake valve (118). See page
2. Loosen the packing nut (102) and plug (123).
3. Use a plastic mallet to tap the piston rod (107)
down, and then pull the rod out through the bottom
of the cylinder.
4. Remove the packing nut (102) and throat pack-
ings.
5. Loosen the jam nut (117). Remove the cylinder
(115) and the o-ring (116*).
6. Clamp the flats of the piston rod in a smooth jaw
vise. Use an open-end wrench to loosen the nut
(110) and then unscrew the piston valve (108).
7. Remove all parts from the piston valve (108).
Reassembling the pump
NOTE: Alternate plastic and leather packings. See Fig.
19. The lips of the throat V-packings face down. The
lips of the piston V-packings face up. Incorrect installa-
tion damages the packings and causes pump leakage.
NOTE: Soak the leather packings in oil before reas-
sembling the pump.
(See Fig. 19.)
1. Check the outside of the piston rod (107) and the
inside of the cylinder (115) for wear. Replace worn
parts to ensure a good seal with the new packings.
2. Stack these parts onto the piston valve (108) one
at a time: the female gland (114*), alternately three
plastic (112*) with two leather packings (113*), and
the male gland (111*). See Fig. 19.
Throat packings
Piston packings
Intake valve
123
102
*103
105*
*104
106*
101
117
*116
115
Fig. 19
107
109*
110
111
*113
112*
114*
108
118
01069A