Graco Inc. 218-745 - Manual (Page 13)

13 307-712
SPRAY PATTERN TROUBLESHOOTING CHART
WARNING
Installing and servicing this equipment requires access to parts which may cause electric shock or other serious
bodily injury if the work is not performed properly. Do not install or service this equipment unless you are trained and
qualified.
To reduce the risk of serious bodily injury, including splashing fluid or solvent in the eyes or on the skin, always follow
the Pressure Relief Procedure Warning on page 9 before checking, adjusting, cleaning or repairing the gun or
any part of the system. Disconnect the fluid hose from the gun.
NOTE: Check all possible remedies in the Troubleshooting Charts before disassembling the gun.
PROBLEM: CAUSE SOLUTION
IMPROPER SPRAY
PATTERN
Insufficient fluid supply. Adjust fluid regulator or fill fluid tank.
Loose fluid nozzle or damaged fluid Tighten or replace fluid nozzle
nozzle taper seat. See page 12.
Dirt between fluid nozzle, taper seat Clean. See page 12.
and body.
Loose or cracked coupler at fluid inlet. Tighten or repair.
Loose fluid tube in cup or tank. Tighten.
Fluid build-up on air cap; partially Clean with soft implement or
clogged horn holes. Full air pressure submerge in suitable solvent and wipe
from clean horn hole forces fan pattern clean. See page 12.
toward clogged end.
Damaged fluid nozzle or air cap holes. Replace damaged part. See page 12.
Fluid build-up on the perimeter of fluid Remove obstruction. Never use wire
nozzle orifice, or partially clogged fluid or hard instruments. See page 12.
nozzle orifice.
Too high atomization air pressure. Reduce air pressure or adjust air
adjusting valve.
Fluid too thin. Regulate fluid viscosity.
Not enough fluid pressure. Increase fluid pressure.
Low atomization air pressure. Increase air pressure.
Fluid too thick. Regulate fluid viscosity.
Too much fluid. Reduce fluid flow. Reduce fluid
pressure on pressure feed guns and/
or adjust fluid adjusting screw until
proper pattern is obtained.
Last coat of fluid applied too wet. Apply drier finish with multiple
strokes.
Too much air pressure. Use least air pressure necessary.
Insufficient air pressure. Increase air pressure.
Non-uniform spray pattern. Clean or replace air cap.
See page 12.
Fluttering or spitting
spray
Streaks
NOTE: Some improper patterns are caused by the improper balance between air and fluid.