Service, Caution, Warning – Graco Inc. UNICARB Pro AA4500 User Manual
Page 29
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Service
Pre-Orifice, Tip Guard, Air Cap, Spray Tip,
or Seat Housing Replacement
1.
Prepare the gun for service as instructed on page
28.
2.
Remove the retaining nut (8), tip guard, (2), air cap
(1), and spray tip (9). See Fig. 7. You may have to
turn the air cap with the tip guard to remove the air
cap from the gun.
3.
Replace the tip gasket (9a) if damaged.
4.
Trigger the gun and remove the seat housing (21)
with the 9 mm driver (64), supplied. See Fig. 8.
CAUTION
The barrel resistor cartridge (B) is part of the barrel
and is not replaceable. To avoid destroying the gun
barrel, do not attempt to remove the barrel resistor
cartridge.
WARNING
FIRE, EXPLOSION, AND
ELECTRIC SHOCK HAZARD
The barrel contact ring (3a) is a conduc-
tive contact ring, not a sealing o-ring. To
reduce the risk of sparking or electric
shock, do not remove the barrel contact
ring from the barrel except to replace it
and never operate the gun without the
contact ring in place. Do not replace the
contact ring with anything but a genuine
Graco part.
5.
Trigger the gun and install the seat housing (21)
with the 9 mm driver (64). Tighten the seat housing
until it’s snug and then tighten it 1/4 turn more.
CAUTION
To avoid damaging the seat housing and gun barrel,
never over-tighten the seat housing. Over-tightening
may result in improper fluid shut-off.
6.
Assemble the spray tip (9), air cap (1), and tip
guard (2). Then install them on the gun, securing
them with the retaining nut (8). Tighten the retain-
ing nut firmly.
CAUTION
To avoid damaging the tip guard (2), orientate the air
cap (1) before tightening the retaining nut (8). Do not
turn the air cap when the retaining nut is tight.
7.
Make sure the electrode is not bent, damaged or
missing from the air cap.
WARNING
ELECTRIC SHOCK HAZARD
To reduce the risk of electric shock or
explosion, never operate the spray gun
with a bent, damaged or missing elec-
trode.
8.
Test the gun resistance as instructed on page 25.
Fig. 7
02004A
9a
9
8
2
1
Fig. 8
21
02035
64
B