Graco 312068M User Manual
Repair
312068M
7
Piston and Cylinder Seals
Disassembly
1.
Relieve pressure, page 3.
2.
Turn OFF the main disconnect and lock out power at
the source.
the source.
3.
Disconnect the pump inlet and outlet lines; see your
proportioner repair manual. Remove the four screws
(30) holding the pump outlet flange (26) to the
hydraulic cylinder. Disconnect pump from drive and
take pump assembly to a workbench.
proportioner repair manual. Remove the four screws
(30) holding the pump outlet flange (26) to the
hydraulic cylinder. Disconnect pump from drive and
take pump assembly to a workbench.
4.
5.
Remove the flange retainer (27), gasket (17), bush-
ing (13), and throat seal (29).
ing (13), and throat seal (29).
6.
Use a soft-faced mallet to help separate pump base
(23) and outlet flange (26) from cylinder (12).
Remove crossover tube (24)
(23) and outlet flange (26) from cylinder (12).
Remove crossover tube (24)
7.
Remove piston from cylinder bore. Remove piston
cap bolt (25), then slide bushing (18) and u-cup seal
(15) from rod.
cap bolt (25), then slide bushing (18) and u-cup seal
(15) from rod.
8.
Thoroughly clean all parts in a compatible solvent
and inspect for wear or damage. Replace as
required.
and inspect for wear or damage. Replace as
required.
Reassembly
1.
Install piston rod seal (15); ensure u-cup faces pis-
ton rod (28) as shown in F
ton rod (28) as shown in F
IG
. 1.
2.
Assemble piston bolt (25) to piston rod (28). Apply
supplied thread sealant to piston bolt and tighten.
See Torque Specification table for torque according
to pump size.
supplied thread sealant to piston bolt and tighten.
See Torque Specification table for torque according
to pump size.
Piston Seal and Cylinder Seal Repair Kits are avail-
able. See Table 1 on page 17 to order the correct
kits for your pump. Also see kit manual 312071.
able. See Table 1 on page 17 to order the correct
kits for your pump. Also see kit manual 312071.
CAUTION
To prevent cross-contamination of the equipment’s
wetted parts, never interchange component A (isocy-
anate) and component B (resin) parts.
wetted parts, never interchange component A (isocy-
anate) and component B (resin) parts.
F
IG
. 1: U-Cup Orientation
F
IG
. 2: Piston Head and Rod
TI9823a
18
15
28
1
Apply supplied sealant to threads.
1
TI9822a
3
15
28
25
#28 Pump Size
28
15
18
1
25
r_24f290_312068
Torque Specification
Pump Size
Torque
30
130 in-lb (14.7 N•m)
28, 40, 48, 60
22 ft-lb (29.7 N•m)
80, 88, 96, 120, 140
45 ft-lb (60.8 N•m)