Graco 25U542, Manual

Page: 33 / 48

Troubleshooting
3A9002A 33
FieldLazer runs, but pump does
not prime or looses prime while in
use.
(Pump cycles but does not pump
paint or build pressure).
Inlet valve check ball is stuck. Press PushPrime button to
dislodge the ball allowing pump to
prime properly.
Prime/Spray Valve is in SPRAY
position.
Turn Prime/Spray Valve down to
PRIME position until paint exits
drain tube. The pump is now
primed.
Pump was not primed with
flushing fluid.
(Thick fluids may not prime if not
initially primed with flushing fluid.)
Remove suction tube from paint.
Prime pump with oil or
water-based flushing fluid. See
page 13.
Debris in paint. Strain the paint. See page 10.
Thick or “sticky” paint. Some fluids may prime faster if
the ON/OFF switch is
momentarily turned off so the
pump can slow and stop. Turn
ON/OFF switch on and off several
times if necessary.
Inlet strainer is clogged or suction
tube is not immersed in paint.
Clean debris off inlet strainer and
make sure suction tube is
immersed in paint.
Inlet valve check ball or seat is
dirty.
Remove inlet fitting. Clean or
replace ball and seat. See page
30.
Suction tube is leaking. Inspect suction tube connection
for cracks or vacuum leaks.
Outlet valve check ball is stuck. Unscrew outlet valve, remove,
and clean assembly.
See Pump Repair , page 29. Then
reprime pump.
Remove inlet and/or outlet valves
and clean, replace and reprime.
See Fill Pump , page 15.
Make certain to not lose the ball
and spring of the inlet valve
assembly or the sprayer will not
function. See Inlet Valve
Removal , page 30.
Make certain the outlet ball moves
free in the housing before
replacing.
Prime/Spray Valve is worn or
obstructed with debris.
Take sprayer to Graco authorized
service center.
Problem Cause Solution