User's Manual

ManualsBrandsGraco ManualsDo-It-Yourself tools311831E

Repair

14 311831E

Repair

Disconnect the Lower

To service the lower, follow the procedure on this page,

and disassemble the lower as described in manual

311832.

1. Relieve the pressure, see Pressure Relief Proce-

dure page 11.

2. Disconnect the hoses from the lower and plug the

ends to prevent fluid contamination.

3. Unscrew the coupling nut (K) from the motor shaft

(F) and remove the collars (G). Remove the cou-

pling nut from the piston rod (H). Unscrew the lock-

nuts (B) from the tie rods (C). Pull the motor (E) off

the lower (D). See F

IG. 6 and FIG. 7.

Reconnect the Lower

1. Assemble the coupling nut (K) to the piston rod (H).

2. Orient the lower (D) to the motor (E). Position the

lower on the tie rods (C). Lubricate the threads of

the tie rods. Screw the tie rod locknuts (B) onto the

tie rods. Tighten the locknuts and torque to 50-60

ft-lb (68-81 N•m).

3. Insert the collars (G) into the coupling nut (K).

Tighten the coupling nut onto the motor shaft (F)

and torque to 145-155 ft-lb (196-210 N•m).

4. Flush and test the pump before reinstalling it in the

system. Connect hoses and flush the pump. While it

is pressurized, check for smooth operation and

leaks. Adjust or repair as necessary before reinstall-

ing in the system. Reconnect the pump ground wire

before operating.

• To service the lower, see manual 311832.

• To service the air motor, see manual 311238.

• To service the hydraulic motor, see manual

308048.

In stand or wall-mounted installations, you do not

have to remove the entire pump from its mounting.

If the tie rods (C) have been disassembled from the

motor, see Reassemble the Tie Rods to the Motor

on page 15.

FIG. 6

NXT Air-Powered

Pump Shown

TI8382b

Torque to 145-155

ft-lb (196-210 N•m).

Torque to 50-60 ft-lb

(68-81 N•m).

Apply lubricant and

PTFE tape.