Displacement Pump

See manual 309277 for pump repair instructions.

Removal

1. Flush pump.

2.

Relieve pressure; page 4.

3.Fig. 8. Remove suction tube and paint hose (re- move at swivel end).

hydraulic rod

pump rod

Installation

WARNING

If pin works loose, parts could break off and project through the air and result in serious injury or prop- erty damage. Make sure pin is properly installed.

CAUTION

If the pump jam nut loosens during operation, the threads of the bearing housing and drive train will be damaged. Tighten jam nut as specified.

1.Fig. 11. Enter Diagnostic (Manual 309378). Short press DTS button to send hydraulic piston rod down. Screw in pump until holes in pump rod and hydraulic rod align.

Fig. 8

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Fig. 11

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4.Fig. 9. Push retaining spring up; push out pin (21).

21

Fig. 9

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5.Fig. 10. Loosen locknut with hammer. Unscrew pump.

2.Fig. 9. Push pin (21) into hole. Push retaining spring into groove.

Fig. 12. Screw pump into hydraulic motor manifold until it is positioned as shown. Back off pump to align pump outlet with hose. Hand tighten jam nut, then tap 1/8 turn with hammer or torque to 150 ft–lb (203 N￿m) (233640/641), 200 ft-lb (271 N￿m).

Flush, within one turn in either direction

Fig. 12

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Fig. 13. Fill packing nut with Graco TSL.

Fig. 10

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Fig. 13

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Hitachi 309379 warranty Displacement Pump, Push retaining spring up push out pin