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Troubleshooting

Check everything in this Troubleshooting table before you bring the sprayer to a Graco authorized service center.

PROBLEM CAUSE SOLUTION
Pump will not prime.
HINT:
SAttemptto free check balls
Spray/Prime valve is set at
SPRAY.
Turn Spray/Prime valve to PRIME (pointing down).
S Attempt to free check balls
by tapping side of inlet valve
as sprayer is stroking.
Spray/Prime valve is plugged Clean/replace drain tube as necessary. See Graco authorized
service center if drain valve is plugged.
as
sprayer
is
stroking.
SStrain paint before spraying
and keep sand and debris
out
Inlet screen is clogged or
suction tube is not immersed.
Clean debris off inlet screen. Make sure suction tube is at
bottom of paint pail.
out
.
S Thoroughly flush after every
paint job.
S Do not store in water. Use
PumpArmor or mineral
Inlet valve check ball is stuck. Remove the tube and place a pencil into the inlet section to
dislodge the ball, allowing the pump to prime properly. OR
Power Flush the unit (page 20).
Pump Armor or mineral
spirits. Outlet valve check ball is
stuck.
Remove hose from sprayer. Unscrew outlet valve to remove
assembly. Gently nudge the ball in the outlet assembly with a
screwdriver. Screw the valve back into the pump.
Power switch is on and
sprayer is plugged in, but
pump does not cycle.
Electrical outlet is not
providing power or extension
cord is damaged or sprayer
power cord is damaged.
Try a different outlet or reset building circuit breaker or replace
extension cord/power cord.
Pressure is set at minimum. Turn Pressure Control Knob to the right (clockwise) to
increase pressure.
Motor or control is damaged. Return sprayer to Graco authorized service center.
Paint is frozen or hardened in
pump.
Unplug sprayer from electrical outlet.
NOTE: If frozen, do not try to start sprayer until
completely thawed, or damage to motor, control board,
and/or drivetrain may occur.
Make sure power switch is OFF. Place sprayer in warm area
for several hours, then plug in and turn on. Slowly increase
pressure setting to see if motor starts.
If paint hardened in sprayer, pump packings, valves, drivetrain,
or pressure switch may need to be replaced.
Cannot pull In–line Valve
trigger.
Trigger safety is in SAFETY
ON position.
Put trigger safety in SAFETY OFF position.
In–line Valve stops spraying. Tip is clogged. Aim In–line Valve into waste pail. Squeeze trigger.
Pump cycles but does not
build up pressure. (i.e., will
not stop cycling even though
Pump check valves are dirty
or damaged.
Clean or replace check valves.
not stop cycling even though
gun trigger is released) Spray/Prime valve is worn or
obstructed with debris.
Return sprayer to Graco authorized service center.
Pump is not primed. See Priming on page 9.
Inlet screen is clogged or
suction tube is not immersed.
Clean debris off inlet screen. Make sure suction tube is at
bottom of pail. Reprime sprayer.
Paint pail is empty. Refill paint pail and reprime sprayer.
Suction tube has vacuum air
leak.
Tighten suction tube connection. Inspect for cracks or vacuum
leaks. If cracked or damaged, replace suction tube.
Pump check ball is stuck. See “Pump will not prime” section of Trouble Shooting
instructions.