Service, Disconnecting the Displacement Pump

Service

WARNING

To reduce the risk of serious injury whenever you are instructed to relieve pressure, always follow the Pressure Relief Procedure on page 9.

1.	Flush the pump if possible. Stop the pump at the
	bottom of its stroke. Relieve the pressure.
2.	Disconnect the air and fluid hoses. Remove the
	pump from its mounting. Note the relative position
	of the pump’s fluid outlet to the air motor’s air inlet.
3.	See Fig. 4. (For Model 221075, refer also to the
	Parts Drawing on page 16.) Unscrew the tie rod
	locknuts (4) from the tie rods (12). Remove the
	cotter pin (3). Unscrew the displacement rod (26)
	from the air motor (14) or connecting rod (37, Mod-
	el 221075 only). Carefully pull the displacement

pump (15) off the air motor (14). Inspect the o-ring

(7).

4. Refer to page 14 for displacement pump service.

To service the air motor, refer to the separate air

motor manual, supplied.

1.	Lubricate the o-ring (7) and place it on the dis-
	placement rod (26). Orient the pump’s fluid outlet
	to the air motor’s air inlet as was noted in step 2
	under Disconnecting the Displacement Pump.
	Position the displacement pump (15) on the tie
	rods (12). See Fig. 4.
2.	Screw the locknuts (4) onto the tie rods (12) loose-
	ly. Screw the displacement rod (26) into the shaft
	of the air motor (14) or the connecting rod (37,
	Model 221075 only) until the pin holes align. Install
	the cotter pin (3).
3.	Mount the pump and reconnect all hoses.
	Reconnect the ground wire if it was disconnected
	during repair. Torque the packing nut/wet-cup (36)
	to 18–20 ft–lb (24–27 N.m). Fill the wet-cup with
	Graco Throat Seal Liquid or compatible solvent.
4.	Tighten the tie rod locknuts (4) evenly, and torque
	as specified in Fig. 4.

President Pumps:

1Torque to 20–30 ft–lb (27–41 N.m) Monark Pumps:

Torque to 15–20 ft–lb (20–27 N.m)

2Torque to 18–20 ft–lb (24–27 N.m)

3Lubricate

3 7

236

5. Start the pump and run it at about 40 psi (3 bar) air

pressure, to check that it is operating properly.

02503

Fig. 4