Graco 334530D Operation And Parts Manual page 29

Problem
Pump output is low
Motor runs but pump does not stroke
Excessive paint leakage into throat
packing nut
Fluid is spitting from gun
334530D
What to Check
If check is OK, go to next
check
Pump rod damage.
Low stall pressure.
Piston packings are worn or
damaged.
O-ring in pump is worn or damaged.
Intake valve ball is packed with
material.
Large pressure drop in hose with
heavy materials.
Check extension cord for correct size. See Extension Cords, page 12.
Connecting rod assembly damaged.
See pump manual.
Gears or drive housing damaged.
Throat packing nut is loose.
Throat packings are worn or
damaged.
Displacement rod is worn or
damaged.
Air in pump or hose.
Spray tip is partially clogged.
Fluid supply is low or empty.
Troubleshooting
What to Do
When check is not OK,
refer to this column
Repair pump. See pump manual.
Turn pressure knob fully clockwise.
Make sure pressure control knob is
properly installed to allow full
clockwise position. If problem
persists, replace pressure transducer.
Replace packings. See pump manual.
Replace o-ring. See pump manual.
Clean intake valve. See pump
manual.
Reduce overall length of hose.
Replace connecting rod assembly.
See pump manual.
Inspect drive housing assembly and
gears for damage and replace if
necessary.
Remove throat packing nut spacer.
Tighten throat packing nut just
enough to stop leakage.
Replace packings. See pump manual.
Replace rod. See pump manual.
Check and tighten all fluid
connections. Cycle pump as slowly as
possible during priming.
Clear tip. See Clear Tip Clog, page
21.
Refill fluid supply. Prime pump. See
pump manual. Check fluid supply
often to prevent running pump dry.
29