
Troubleshooting
3A2247A 11
Gas engine / electric motor operates
but displacement pump does not
operate
Hydraulic pump valve is OFF Set hydraulic pump valve ON.
Pressure setting too low Increase pressure, page Operation manual.
Displacement pump outlet filter (if used)
is dirty or clogged
Clean the filter.
Tip or tip filter (if used) is clogged Remove tip and/or filter and clean.
Hydraulic fluid too low Shut off sprayer. Add fluid*.
Belt is off pulley, worn or broken Replace. See Repair manual.
Hydraulic pump worn or damaged Bring sprayer to Graco distributor for repair.
Dried paint seized paint pump rod Service pump. See manual 311845.
Hydraulic motor not shifting Set pump valve OFF. Turn pressure down. Turn
engine OFF. Pry rod up or down until hydraulic
motor shifts. See Repair manual.
For 3 Phase electric motor only: Red
phase sequence light is ON, indicating
motor rotating in the wrong direction
Remove plug from receptacle and rotate plug
phase screw. See Operation manual.
Displacement pump operates, but
output is low on upstroke
Piston ball check not seating properly Service piston ball check. See manual 311845.
Piston packings worn or damaged Replace packings. See manual 311845.
Displacement pump operates but
output is low on downstroke and/or
on both strokes
Piston packings worn or damaged Tighten packing nut or replace packings.
See manual 311845.
Intake valve ball check not seating
properly
Service intake valve ball check. See manual
311845.
Displacement pump air leak
Paint leaks and runs over side of
wetcup
Loosen wet-cup Tighten wet-cup enough to stop leakage.
Throat packings worn or damaged Replace packings. See manual 311845.
Excessive leakage around hydraulic
motor piston rod wiper
Piston rod seal worn or damaged Replace these parts. See Repair manual.
Fluid delivery is low Pressure setting too low Increase pressure, see Operation manual.
Displacement pump outlet filter (if used)
is dirty or clogged
Clean filter.
Hydraulic motor is worn or damaged Bring sprayer to Graco distributor for repair.
Large pressure drop in fluid hose Use larger diameter or shorter hose.
Sprayer overheats Paint build up on hydraulic components Clean hydraulic components.
Oil level is low Fill with oil. See Operation manual.
Inlet to hydraulic pump pulley/cooling fan
is obstructed
Remove obstructions.
Inlet to 3 phase electric motor cooling fan
is obstructed.
Remove obstructions.
Spitting from gun Air in fluid pump or hose Check for loose connections on siphon
assembly, tighten, then reprime pump.
Fluid supply is low or empty Refill supply container.
Excessive hydraulic pump noise Low hydraulic fluid level Turn sprayer OFF. Add fluid*.
Air in hydraulic lines Bleed lines. See Repair manual.
*Check hydraulic fluid level often. Do not allow it to become too low. Use only Graco approved hydraulic fluid.
PROBLEM CAUSE SOLUTION