5
306–646
OPERATION
WARNING
Pressure Relief Procedure
To reduce the risk of serious bodily injury, including
fluid injection, splashing in the eyes or on the skin,
or injury from moving parts, always follow this pro-
cedure whenever you shut of f the pump, when
checking or servicing any part of the spray/dis-
pensing system, when installing, cleaning or
changing spray tips/nozzles, and whenever you
stop spraying/dispensing.
1. Engage the gun/valve safety latch.
2. Shut off the air to the pump.
3. Close the bleed–type master air valve (re-
quired in your system).
4. Disengage the gun/valve safety latch.
5. Hold a metal part of the gun/valve firmly to the
side of a grounded metal pail, and trigger the
gun/valve to relieve pressure.
6. Engage the gun/valve safety latch.
7. Open the drain valve and/or the pump bleeder
valve (required in your system), having a con-
tainer ready to catch the drainage.
8. Leave the drain valve open until you are ready
to dispense again.
If you suspect that the spray tip/nozzle or hose is
completely clogged, or that pressure has not been
fully relieved after following the steps above,
VERY SLOWLY loosen the tip guard retaining nut,
nozzle or hose end coupling and relieve pressure
gradually, then loosen completely. Now clear the
tip/nozzle or hose.
Moving parts can pinch or amputate your fingers or
other body parts. When the pump is operating, the
priming piston (located at the pump intake) and the
air motor piston (located behind the air motor shield)
move. Therefore, NEVER operate the pump with
the air motor shield removed, and keep your fingers
and hands away from the priming piston.
Before attempting to clear an obstruction from the
priming piston or service the pump, follow the
Pres-
sure Relief Procedure Warning
above to prevent
the pump from starting accidentally.
WARNING
Flush the Pump Before Using
This pump was tested with lightweight motor oil which
was left in to protect the pump parts. To prevent contami-
nation of the fluid being pumped, flush the pump with a
compatible solvent before using it. If the pump is being
used to supply a circulating system, allow the solvent to
circulate until the pump and lines are thoroughly flushed.
Keep the packing nut/wet–cup (21) one–half full with
Graco Throat Seal Liquid (TSL), to help prevent the fluid
being pumped from drying on the displacement rod and
damaging the packings.
Starting and Adjusting the Pump
1. Make sure the air regulator (C), drain valve (H), and
pump bleeder valve (4) are closed.
2. Open the bleed–type master air valve (D).
3. Hold a metal part of the gun/valve firmly to the side of
a grounded metal pail, and trigger the gun/valve.
4. Slowly open the air regulator (C) until the pump starts
running slowly and smoothly (about 20 psi [1.4 bar]).
Cycle the pump slowly until all the air is purged from
the pump and lines.
5. If the pump is not priming properly, open the bleeder
valve (4) slightly. Do not open it all the way; the han-
dle can come off. Cover the bleeder valve hole with
something
other than your hand or fingers
and
use it as a priming valve until the fluid appears at the
bleeder hole. Close the bleeder valve.
To reduce the risk of fluid injection, DO NOT use
your hand or fingers to cover the bleeder hole when
priming the pump.
WARNING
6. Release the trigger and engage the safety latch. The
pump will stall against pressure.
7. In a direct supply system, the pump will start and stop
as the gun/valve is opened and closed. In a circulat-
ing system, it will run continuously and speed up or
slow down as the system demands. Always use the
lowest pressure necessary to obtain the desired re-
sults.
To reduce the risk of serious bodily injury, including
fluid injection and splashing in the eyes or on the
skin, and property damage, never exceed the maxi-
mum air and fluid working pressure of the lowest
rated component in your system.
See EQUIPMENT
MISUSE HAZARD, System Pressure,
on page 3.
WARNING
Never allow the pump to run dry of the fluid being
pumped. A dry pump will quickly accelerate to a high
speed, possibly damaging itself. If your pump acceler-
ates quickly, or is running too fast, stop it immediately and
check the fluid supply . If the supply container is empty
and air has been pumped into the lines, prime the pump
and the lines with fluid, or flush the pump and leave it filled
with a compatible solvent. Be sure to eliminate all air from
the fluid system.
NOTE:
A pump runaway valve (F) can be installed on
the air line to automatically shut off the pump if it
starts to run too fast.
