Gun Operation Troubleshooting - Graco PRO AA4500 Instructions-Parts List Manual

Gun Operation Troubleshooting
PROBLEM
Leakage from fluid needle
area
Air leakage from front of gun
Fluid leakage from front of
gun
"Orange Peel" finish
Excessive spray fog
No
fluid sprays from gun
Equipment covered with
fluid
?aint build-up on air cap
-hid doesn't shut off
xoperly
CAUSE
Tighten packing nut
Fluid needle packings loose
SOLUTION
Lubricate O-ring
Air valve O-ring sticking
Clean; sewice Air valve not seating properly
Replace fluid needle assembly Fluid needle packing damaged
Worn fluid needle
Loose or worn fluid seat
Loose spray tip
Damaged tip seal
Replace fluid needle assembly
Tighten or replace fluid seat
Tighten retaining nut
Replace tip seal
Insufficient air pressure
Using too large of a spray tip
Fluid poorly mixed or filtered
Improper thinner beina used
increase air pressure with gun air con-
trol valve or with gun air regulator; Use
least air pressure needed for good
results
Use a smaller size spray tip
Remix or refilter fluid
Use proper thinner
~~~ ~~~
Too much air pressure
Fluid thinned too much
Fluid low
valve or with gun air regulator: Use
Reduce air pressure with gun air control
least air pressure needed for good
results
Properly thin fluid
Check; Add fluid if necessary
Dirty or clogged spray tip
Check for proper CFM; Check baffles
Booth exhaust air flow insufficient or
Replace fluid needle assembly
Broken fluid needle
Check: Replace spray tip
Damaged spray tip
Clean spray tip
not directed properly
and direction of air flow
Improper distance between gun and
workpiece
Too much air pressure
Adjust spraying distance to 8 to 12
inches (203 to
305
mm).
Reduce air pressure with gun air control
valve or with gun air regulator
Seat housing over-tightened
Fluid leakage buildup on fluid
Replace seat housing
needle
Replace fluid needle
~~
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