Graco 205394, Instructions-Parts List Manual

Page: 7 / 18

Troubleshooting
306674W 7
Troubleshooting
1. Follow Pressure Relief Procedure , page 6, before
checking or repairing gun.
2. Check all possible problems and causes before dis-
assembling gun.
* Follow the Pressure Relief Procedure (see page 6), and disconnect the fluid line. If the pump starts when the air is
turned back on, the fluid line, hose, valve, etc. was clogged.
Problem Cause Solution
Pump fails to operate
Inadequate air supply pressure or
restricted air lines.
Increase air supply; clear
Closed or clogged valves Open; clean
Clogged fluid lines, hoses, valve,
etc.
Clear*
Damaged air motor Service air motor
Exhausted fluid supply Refill and reprime, or flush
Continuous air exhaust
Worn or damaged air motor gasket,
packing, seal, etc.
Service air motor
Erratic pump operation
Exhausted fluid supply Refill and reprime, or flush
Held open or worn intake valve or
piston packings
Clear; service
Pump operates, but output low on
upstroke Held open or worn piston or pack-
ings
Clear; service
Pump operates, but output low on
downstroke
Held open or worn intake valve Clear; service
Pump operates, but output low on
both strokes
Inadequate air supply or restricted
air lines
Increase air supply; clear
Closed or clogged valves Open; clean
Exhausted fluid supply Refill and reprime, or flush
Clogged fluid lines, hoses, valves,
etc.
Clear*
Packing nut too tight Loosen
Loose packing nut or worn packings Tighten; replace