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Troubleshooting
Gun Operation Troubleshooting
PROBLEM
CAUSE
SOLUTION
Fluid leakage from the fluid packing
area
The fluid rod packings or fluid rod are
worn.
Replace the packings or rod; see page
32.
Fluid leakage from the front of the
gun
The fluid rod is worn or damaged.
The fluid seat is worn.
The resistor stud is loose.
The fluid nozzle is loose.
The resistor stud o-ring is damaged.
Replace the fluid rod; see page 32.
Replace the fluid nozzle and/or electrode
needle; see page 30 and 31.
Tighten the resistor stud; see page 30.
Tighten the fluid nozzle; see page 30.
Replace the o-ring; see page 30.
“Orange Peel” finish
The air pressure is insufficient.
The fluid is poorly mixed or filtered.
An improper thinner is being used.
Increase the air pressure; use the least air
pressure needed for good results.
Remix or refilter the fluid.
Use the proper thinner.
Excessive spray fog
The air pressure is too high.
The fluid is thinned too much.
Reduce the air pressure; use the least air
pressure needed for good results.
Properly thin the fluid.
No fluid sprays from the gun
The fluid supply is low.
The fluid nozzle is dirty or clogged.
The fluid nozzle is damaged.
The piston is not actuating.
The actuator arm is out of position.
Check the fluid supply; add fluid if
necessary.
Clean the fluid nozzle; see page 22.
Replace the fluid nozzle; see page 30.
Check the cylinder air; check the piston
u-cup; see page 33.
Check the actuator arm and nuts; see
page 34.
The equipment is covered with fluid
The exhaust air flow is insuf ficient or not
directed properly.
The distance between the gun and work-
piece is incorrect.
Check for the proper CFM; check the
baffles and direction of the air flow.
Adjust the spraying distance to 8 to 12
inches (203 to 305 mm).
Dirty air cap
The electrode is bent.
The nozzle orifice is damaged.
The fluid is coming on before the air.
The air cap and fluid nozzle are mis-
aligned.
Air
Cap
Fluid
Nozzle
ALIGNED
MISALIGNED
Straighten the electrode.
Replace the fluid nozzle; see page 30.
Check the actuator arm and nuts; see page
34.
Check the air cap and fluid nozzle seat for
fluid buildup. Clean or replace parts as
needed; see page 22 or 30.
Air leakage from the air cap
The o-rings on the piston stem are worn.
Inspect the o-rings; replace them as
needed; see page 33.
Air leakage from the manifold
The manifold gasket is damaged, or the
manifold is not tight.
Replace the gasket or tighten the manifold
screws; see page 39.
Fluid leakage at the quick-disconnect
The manifold is not tight.
The o-rings on the fluid hose are worn or
missing.
Tighten the manifold screws; see page
39.
Inspect or replace the o-rings.