Graco GX21 Cordless Operation, Parts page 36

Troubleshooting
Problem
Sprayer runs, but pump does not prime
or looses prime while in use.
(Pump cycles but does not pump paint
or build pressure.)
36
Cause
Inlet valve check ball is stuck.
Prime/Spray Valve is in SPRAY
position.
Pump was not primed with flushing fluid.
(Thick fluids may not prime if not initially
primed with flushing fluid.)
Debris in paint.
Thick or "sticky" paint.
Inlet strainer is clogged or suction tube
is not immersed in paint.
Inlet valve check ball or seat is dirty.
Suction tube is leaking.
Outlet valve check ball is stuck.
Prime/Spray Valve is worn or obstructed
with debris.
Solution
Press PushPrime button to dislodge the
ball allowing pump to prime properly,
OR Power Flush sprayer, see page 25.
Turn Prime/Spray Valve down to PRIME
position until paint exits drain tube. The
pump is now primed.
Remove suction tube from paint. Prime
pump with oil or water-based flushing
fluid. See page 14.
Strain the paint. See page 11.
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.
Clean debris off inlet strainer and make
sure suction tube is immersed in paint.
Remove inlet fitting. Clean or replace
ball and seat. See page 33.
Inspect suction tube connection for
cracks or vacuum leaks.
Unscrew outlet valve, remove, and
clean assembly.
Take sprayer to Graco authorized
service center.
3A8429A