Graco Fluid Automation 633, Operation, Page: 44 / 51

Testing Procedures
44 332078C
Testing Procedures
Pump Testing
If the machine is suspected of pumping inaccurately, fol-
low these procedures to check each pump.
At normal operating pressure, test if the pump is leaking
inside, which will cause one pump to run at a higher
pressure than the other. Follow these steps.
1. Enter into “Auto Mode” and verify the machine per-
forms a refill.
2. Navigate to the “Monitor” screen and observe the
material pressures after the fill valves close.
NOTE: If the pressure on either side drops by 100 psi
(0.7 MPa, 7 bar) or more, the pump may be leaking
internally. Refer to
Troubleshooting , page 45, for pos-
sible solutions to pump leakage.