Graco Troubleshooting for XP70 Paint Sprayers

Troubleshooting

Troubleshooting

				✖ Fluid ratio will be wrong.
				◆ Purge all air from system before proportioning
				fluids.
	Problem		Cause		Solution
System stops or will not start.		Air pressure or volume too low.			Increase; check air compressor.
		Closed or restricted air line or air			Open or clean.
		valve.
		Fluid valves closed.			Open.
		Clogged fluid hose.			Replace.
		Air motor worn or damaged.			Repair air motor; see 311238.
		Displacement pump stuck.			Repair pump; see 311762.
System speeds up or runs erratically.		Fluid containers are empty.◆			Check often; keep filled.
		Air in fluid lines.◆			Purge; check connections.
		Displacement pump parts worn or			Repair pump; see 311762.
		damaged.
Pump operates, but resin output		Dirty, worn, or damaged resin pump			Clean, repair pump; see 311762.
pressure drops on upstroke.✖		piston valve or piston packings.
Pump operates, but resin output		Dirty, worn, or damaged resin pump			Clean, repair pump; see 311762.
pressure drops on downstroke.		intake valve.
Pump operates, but resin output		Hardener output restriction.			Clean, unplug hardener side. Open
pressure drops on both strokes.✖					manifold restrictor.
		Fluid supply low.◆			Refill or change container.
Pump operates, but hardener output		Dirty, worn, or damaged hardener			Clean, repair pump; see 311762.
pressure drops on upstroke.✖		pump piston valve or piston packings.
Pump operates, but hardener output		Dirty, worn, or damaged hardener			Clean, repair pump; see 311762.
pressure drops on downstroke.✖		pump intake valve.
Pump operates, but hardener output		Resin output restriction.			Clean, unplug resin side.
pressure drops on both strokes.
		Fluid supply low.◆			Refill or change container.
Fluid leak in packing nut.		Loose packing nut or worn throat			Tighten; replace; see 311762.
		packings.
Fluid leak under packing nut		Packing cartridge o-ring.			Replace o-ring; see 311762
Relief valve (AM) leaks back to sup-		Relief valve is dirty or damaged.			Replace valve cartridge (302) with kit
ply, opens too soon, or will not close.					262520.
No pressure on hardener side; fluid		Overpressure rupture disk blown.			Determine cause of overpressuriza-
leaking from hardener pump outlet					tion and correct. Replace rupture disk
rupture disc fitting.					assembly (140) and over-pressure
					cartridge (302).
Pressure and flow surges on		Feed pressure too high. Every pound			Reduce feed pressure. See Techni-
upstroke.		of feed pressure adds 2 psi boost			cal Data, page 53.
		during upstroke.

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