Graco 18H269 Operation Manual page 31

Problem
Pump output is low
Motor runs but pump does not
stroke
Excessive paint leakage into
throat packing nut
Fluid is spitting from gun
3A9031D
What to Check
If check is OK, go to next
check
Pump rod damage.
Low stall pressure (pressure
setting too low).
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.
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 control.
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 23.
Refill fluid supply. Prime
pump. See pump manual.
Check fluid supply often to
prevent running pump dry.
31