Replacement Part List
Basic Troubleshooting
312667K 15
Pump cycles but does not build up 
pressure.
Prime/Spray valve in PRIME position 
(pointing down).
Turn Prime/Spray valve to SPRAY 
position (pointing forward).
Pump is not primed. Prime pump, see Operation manual 
312001.
Inlet screen is clogged or suction 
tube is not immersed.
Clean debris off inlet screen and 
make sure suction tube is immersed 
in fluid.
Suction tube is leaking, allowing air to 
enter.
Check suction tube for cracks and 
cuts. Make sure suction tube clamp is 
on hose. Replace suction tube if 
cracked or damaged.
Prime/Spray Valve is worn or 
obstructed with debris.
Take sprayer to Graco/M
AGNUM 
authorized service center.
Pump check ball is stuck. Read Pump does not prime section 
in Troubleshooting, page 14.
Pump cycles, but paint only dribbles 
or spurts when spray gun is trig-
gered.
Pressure is set too low. Slowly turn pressure control knob 
clockwise to increase pressure set-
ting which will turn motor on to build 
pressure.
Spray tip is clogged. Unclog spray tip, see Operation man-
ual 312001.
InstaClean fluid filter is clogged.
(ProX7 and ProX9 Only)
Clean or replace InstaClean fluid fil-
ter, see Operation manual 312001.
Spray gun fluid filter is clogged. Clean or replace gun fluid filter, see 
Operation manual 312001.
Spray tip is too large or worn. Replace tip.
Problem Cause Solution










