Graco 311211L important safety instructions Preventive Maintenance Schedule

Maintenance

Preventive Maintenance

Schedule

The operating conditions of your particular system determine how often maintenance is required. Establish a preventive maintenance schedule by recording when and what kind of maintenance is needed, and then determine a regular schedule for checking your system. Your maintenance schedule should include the follow- ing:

Flushing

• Flush before shutting down the system for an extended period of time.

•Flush before repairing the pump, if possible.

•Flush before fluid can dry out, settle, or set up in the equipment.

Air Line Filter

Drain and clean as necessary.

Hydraulic Power Supply Check

Carefully follow the hydraulic power supply manufac- turer's recommendations on reservoir and filter cleaning, and periodic changes of hydraulic fluid.

Mix Tank Volume

Don't let the mix tank run dry. When the tank is empty, the pump demands more power as it tries to suck in some fluid. This causes the pump to run too fast, which can seriously damage the pump.

Packing Nut Tightness

Check the packing nut (21) tightness every few days at startup and then weekly throughout the life of the throat seal. The packing nut should be tight enough to stop leakage, but no tighter. See FIG. 4.

To check the adjustment of the packing nut, stop the pump and relieve fluid pressure. Loosen the packing nut until it turns freely. Tighten the nut firmly and then turn the nut another 1/4 turn. If you have a torque wrench, tighten the packing nut to 30 ft-lb (40 N•m), then back off and re-tighten to 15-20 ft-lb (20-27 N•m).

Maintenance

Excessive Leaking at Throat

If you see excessive leaking at the throat, tighten the packing nut (21), see FIG. 4. If this does not fix the prob- lem, replace the throat packings, piston rod, or both See manual 311690.

NXT Air-Powered

Pump Shown

1packing nut

1 Torque to 15-20 ft-lb (20-27 N•m). TI8354a

FIG. 4

311211L 13