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.

 

 

 

 

 

 

 

 

 

 

 

 

 

3A0420H

31

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Image 31
Graco XP70 important safety instructions Troubleshooting, Problem Cause Solution