Service; Read This Page Before Servicing The Gun - Graco PRO AA4500 Instructions Manual

WARNING
Installing and servicing this equipment requires
access to parts that may cause electrostatic shock
or other serious bodily injury if the work is not per-
formed properly. Do not install or service this equip-
ment unless you are trained and qualified.
NOTE: Check all possible remedies in Troubleshoot-
ing before disassembling the gun.
Flush the Gun and Relieve Pressure
WARNING
To reduce the risk of fire, explosion, or electrostatic
shock, be sure the ES ON-OFF lever is turned to
OFF before flushing the gun.
CAUTION
Methylene chloride is not recommended as a flush-
ing or cleaning solvent with this gun as it will dam-
age nylon components.
Flush and clean the gun as described on page 16. Fol-
low the Pressure Relief Procedure Warning at right
then disconnect the air and fluid hose from the gun.
Service Notes:
If the plastic parts of the gun must be held in a vise,
only use padded vise jaws to avoid damaging parts.
Always remove the gun from the worksite for serv-
ice or repair. The service or repair area must be
clean.
When servicing the PRO AA4500 Gun, make sure
you do not mix or use other PRO Gun parts that
may look similar, but have different part numbers.
See the WARNING at right. Note that the air cap,
spray tip, and tip guard for this gun are orange.
Tools Needed
2 mm Driver (included with gun)
4 mm Driver (included with gun)
9 mm Driver (included with gun)
Adjustable Wrench
Medium Screw Driver
Snap Ring Pliers
Needle Nose Pliers

Service

Read This Page Before Servicing the Gun!

WARNING
Pressure Relief Procedure
To reduce the risk of serious injury, including fluid
injection, splashing in the eyes or on skin, or elec-
trostatic shock, always follow this procedure when-
ever the pump is shut off, when checking or servic-
ing any part of system, when installing or changing
spray tips and whenever you stop spraying.
1. Lock the spray gun trigger safety latch. See
Fig. 3.
2. Turn the gun's ES ON-OFF lever to the OFF
position.
3. Shut off the power to the pump.
4. Close the bleed-type master air valve (required
in system).
5. Close the air valve for the gun air supply line.
6. Unlock the gun trigger safety latch.
7. Trigger the gun into a grounded metal waste
container to relieve fluid and air pressure.
8. Lock the gun trigger safety latch again.
9. Open the pump drain valve (required in sys-
tem) to help relieve fluid pressure in the dis-
placement pump. In addition, open the drain
valve connected to the fluid pressure gauge (in
a system with fluid regulation) to help relieve
fluid pressure in the hose and gun. Triggering
the gun to relieve pressure may not be suffi-
cient. Have a container ready to catch the
drainage.
10. Leave the drain valve(s) open until you are
ready to spray again.
If you suspect that the spray tip or hose is com-
pletely clogged or that pressure has not been fully
relieved after following the steps above, v ery slowly
loosen the hose end coupling and relieve pressure
gradually, then loosen completely. Now clear the tip
or hose obstruction.
PRO Gun Non-interchangeable Parts
WARNING
Some PRO AA4500 Gun replacement parts look
similar to other PRO Gun parts but are not inter-
changeable! When servicing, do not mix or use
other PRO Gun parts that may look similar, but
have different part numbers! Use of parts other
than those specified in the PRO AA4500 Gun parts
list on page 39 could alter the grounding continuity
of the gun, cause parts to leak or rupture, or cause
the gun to malfunction and result in serious injury,
fire, explosion or property damage.