Fluid Pump Runs Constantly - Graco GMAX 3400 Operation

Fluid Pump Runs Constantly

1. Perform Pressure Relief Procedure, page 13, turn
prime valve forward to SPRAY position, and turn
power switch OFF.
2. Remove control box cover.
Troubleshooting Procedure:
With a pressure gauge plumbed into the paint
hose, start the engine. Turn pump switch ON.
Does sprayer exceed maximum pressure?
YES
Disconnect clutch wires from control board (see
diagram, page 36). Does the pump stop
running?
YES
Make sure clutch wires are plugged in (see
diagram, page 36). Do the clutch test points
read 10-18 DC volts?
YES
Unplug transducer from control board.
YES
Bad transducer.
Replace and test with a new one.
3A6400A
Pump problem. See the proper fluid pump
manual for the sprayer for further
NO
troubleshooting procedures.
Mechanical problem in the clutch pinion
NO
assembly (clutch may be close to the
Check for a short from the two clutch wires
NO
to the frame. If shorted, repair or replace
faulty wire.
Replace the control board.
NO
Troubleshooting
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