Graco HIGH-FLO 311211L - Manual (Page 13)

Maintenance
311211L 13
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
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 F
IG . 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).
Excessive Leaking at Throat
If you see excessive leaking at the throat, tighten the
packing nut (21), see F
IG . 4. If this does not fix the prob-
lem, replace the throat packings, piston rod, or both See
manual 311690.
• 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.
F IG . 4
NXT Air-Powered
Pump Shown
TI8354a
1
Torque to 15-20 ft-lb (20-27 N•m). 1
packing nut