Service - Graco 907-292 Instructions-Parts List Manual

SERVICE
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Installing and servicing this equipment requires access to parts which may cause electric shock or other serious
bodily injury. Do not install or service this equipment unless you are qualified.
Before servicing the tip or gun, and before disassembling the gun, ALWAYS follow the Pressure Relief Pro-
cedure on page
2.
Disconnect the fluid hose from the gun.
NOTE:
Check all of the possible remedies in the Troubleshooting Charts before disassembling the gun.
SPRAY PATTERN TROUBLESHOOTING CHART
PROBLEM:
IMPROPER SPRAY
PATTERN CAUSE
SOLUTION
Fluttering or Insufficient fluid supply Adjust fluid regulator or fill tank.
Spitting spray
Leak in the fluid line Tighten or repair
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Dry or worn fluid needle packing or loose packing
Lubricate or replace packing, tighten
nut permits air to get into fluid passage. packing nut.
Loose fluid tip or damage fluid tip taper seat. Tighten or replace fluid tip.
Dirt between fluid tip, taper seat and body. Clean.
Fluid build up on air cap; partially clogged horn
Clean with soft brush or submerge in
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:?
holes. Full air pressure from clean horn hole
suitable solvent and wipe clean.
forces fan panern toward clogged end
Damaged fluid tip or air cap holes
Replace damaged part.
e
~
Fluid build up on the perimeter of fluid tip orifice, Remove obstruction. Never use a wire or
or partially clogged fluid tip orifice hard instruments.
Too high atomization air pressure
Reduce air pressure or adjust air adjusting
valve.
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Fluid too thin Regulate fluid viscosity.
Not enough fluid pressure
Increase fluid pressure.
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Low atomization air pressure Raise air pressure.
Fluid too thick Regulate fluid viscosity.
Too much fluid Reduce fluid flow, reduce fluid pressure
0
on pressure feed guns and/or adjust fluid
adjusting screw until proper pattern is
obtained.
Streaks
Last
coat of fluid applied too wet Apply drier finish with multiple strokes.
;8.
':':
Too much air pressure
Use least air pressure necessary.
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i
Insufficient air pressure Increase air pressure.
Non-uniform spray pattern
Clean or replace air cap.
NOTE:
Some improper patterns are caused by the improper balance between air and fluid.
8 307-896