Graco EFR Instructions - Parts Manual page 24

Troubleshooting
Problem
General
Material imbalance
Erratic pump movement
Pump output low
24
Cause
Inadequate flow from pump;
Pump cavitation
Obstructed fluid hose or dispense
valve; fluid hose ID too small
Worn piston valve or intake valve in
displacement pump
Inadequate feed pump pressure
Solution
Increase fluid supply to proportion-
ing pump:
• Use minimum 3/4 in. (19 mm) ID
supply hose, as short as practi-
cal
Clean inlet strainer screen
Worn pump inlet valve ball/seat or
gasket
Feed pump pressure is too low.
Adjust pressure to maintain 100 psi
(0.7 MPa, 7 bar) minimum.
Open, clear; use hose with larger ID
See pump manual 3A0019
Check feed pump pressure and
adjust to 100 psi (0.7 MPa, 7 bar)
minimum
3A6165A