Graco 257100, Operation

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Troubleshooting
16 3A0245A
Low or Fluctuating Output
PROBLEM CAUSE SOLUTION
Low output Pump is worn or clogged. Service pump. Check piston and intake
valves for wear or obstructions.
Material hose length. Longer hose
length reduces drywall feed pump per-
formance. Reduce hose length or thin material.
Use 20A setting if available.
Pump hopper adapter connections are
loose. Tighten any loose connections.
Replace pump hopper adapter if
cracked or punctured.
Check electrical supply voltage with volt
meter. Meter must read:
210-255 Vac for 220-240 Vac models;
85-130 Vac for 100-120 Vac models.
Low voltages reduce drywall feed pump
performance. Try a different outlet.
Extension cord size and length; must be
at least 12 awg (1.0 mm2) wire and no
longer than 90 m (295 ft). Longer cord
lengths reduce drywall feed pump
performance. Replace with a correct, grounded
extension cord.
Leads from motor to flow control circuit
board for damaged or loose wires or
connectors. Inspect wiring insulation
and terminals for signs of overheating. Be sure male terminal blades are cen-
tered and firmly connected to female
terminals. Replace any loose terminal
or damaged wiring. Securely reconnect
terminals.
Flow control knob is turned down. Turn flow control knob fully clockwise.
Make sure flow control knob is properly
installed to allow full clockwise position.
Plugged prime/tool fill/ recirculation
valve Material has dried and plugged the
prime/tool fill/ recirculation valve. Aim hose into waste pail. Turn prime
valve handle from TOOL FILL to PRES-
SURE RELIEF and then back to TOOL
FILL. If valve remains plugged, see
Pressure Relief Procedure, page 6.
Plugged hose, swivel, tool, or inline
valve Debris or pack-out in tool, swivel, hose,
or inline valve Check and clean out all flow compo-
nents. Perform Pressure Relief Proce-
dure, page 6.