SERVICE BULLETIN
SB-2-179-F
Replaces SB-2-179-E
Repair Kit KK-5025
DESCRIPTION
The GFG-517 is a general purpose, heavy
duty, high production spray gun suitable for
use with most types of materials. The fluid
tip and needle and internal fluid passages
are stainless steel.
Note
This gun includes 300 series stain-
less steel fluid passages and 400/
300 S.S. series tip and needle.
Guns may be used with chlorinated
solvent materials. The gravity cup
must also be compatible for use
with chlorinated solvent materials
(GFC-501 Acetal).
IMPORTANT: This gun is designed for use
with mildly corrosive and non-abrasive ma-
terials. If used with other high corrosive or
abrasive materials, it must be expected
that frequent and thorough cleaning will
be required and the necessity for replace-
ment of parts will be increased.
Note
The GFC gravity feed cups are in-
cluded with the gun as part of the
GFG-618 gun and cup kits. See
Accessories on page 6 for more
information.
INSTALLATION
1 .
Attach the air supply line to the air inlet
(18). An air transformer installed as
close as possible to the gun will provide
filtered and regulated air.
Note
When larger diameter air hoses are
used, it is advisable to use an 8' or
10' "whip end" or a smaller diam-
eter hose at the gun for greater
flexibility or movement.
2.
Attach the gravity feed cup to the
material inlet.
Note
Protective coating and rust inhibi-
tors have been used to keep the
gun in good condition prior to ship-
ment. Before using the gun, flush it
with solvents so that these materi-
als will be removed from fluid pas-
sages.
OPERATION
Mix, prepare and strain the material to be
sprayed according to the paint
manufacturer's instructions.
Strain material through a 60 or 90 mesh
screen.
1 .
Fill the gravity feed cup with the ma-
terial. Do not overfill. Make sure that
the cup lid vent hole is clear.
2 .
Turn on the air at the source of supply.
Adjust the atomization air pressure to
35 psi.
3 .
Open the spreader adjustment valve
(19) (Fan) by turning the valve stem
counter-clockwise.
4 .
Close the fluid needle adjusting screw
(25) by turning clockwise.
5 .
Spray a test area by turning the fluid
needle adjusting screw (25) counter-
clockwise until a full coat is obtained.
If the finish is too sandy and dry, the
material flow may be too low for the atomi-
zation air pressure being used.
If the finish sags, there is too much material
flowing for the atomization air pressure
being used.
Both of the above can be corrected by
increasing or decreasing the atomization air
pressure or the material flow. Pattern width
can be altered by turning the spreader
adjustment valve (19), either clockwise to
decrease the width or counter-clockwise to
increase the width.
GFG
TM
GRAVITY PRO
TM
MODEL GFG-517
CONVENTIONAL SPRAY GUN
IMPORTANT: Before using this
equipment, read all safety precautions
and instructions. Keep for future use.
PREVENTIVE MAINTENANCE
To clean air cap and fluid tip, brush exterior
with a stiff bristle brush. If necessary to
clean cap holes, use a broom straw or
toothpick.
Never use a wire or hard instru-
ment.
This may scratch or burr holes caus-
ing a distorted spray pattern.
To clean fluid passages, remove excess
material from cup, then flush with a suitable
solvent. Wipe gun exterior with a solvent
dampened cloth. Never completely immerse
in solvent as this is detrimental to the
lubricants and packings.
Note
When replacing the fluid tip or fluid
needle, replace both at the same
time. Using worn parts can cause
fluid leakage. Tip and needle sets
are available. See Chart 2. Also,
replace the needle packing at this
time. Lightly lubricate the threads
of the fluid tip before reassembling.
Torque to 12-15 ft. lbs. Do not over-
tighten the fluid tip.
To prevent damage to the fluid tip (2)
or fluid needle (2), be sure to either 1)
pull the trigger and hold while tight-
ening or loosening the fluid tip or 2)
remove fluid needle adjusting screw
(25) to relieve spring pressure against
needle collar.
SPRAY GUN LUBRICATION
Daily, apply a drop of SSL-10* spray gun
lube at trigger bearing stud (15) and the
stem of the air valve (10) where it enters the
air valve assembly (13). The shank of the
fluid needle (2) where it enters the packing
nut (6) should also be oiled. The fluid needle
packing (5) should be lubricated periodi-
cally. Make sure the baffle (4) and retaining
ring (1) threads are clean and free of for-
eign matter. Before assembling retaining
ring to baffle, clean the threads thoroughly,
then add two drops of SSL-10 spray gun
lube to threads. The fluid needle spring (22)
and air valve spring (11) should be coated
(Continued on page 3)
