12
307-928
OPERATION-MAINTENANCE
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 proce-
dure whenever you shut off the pump, when check-
ing or servicing any part of the spray system, when
installing, cleaning or changing spray tips, and
whenever you stop spraying.
1. Engage the spray gun safety latch.
2. Shut off the main power to the heater, if used.
Circulate the fluid for at least 10 minutes to allow
it and the heater to cool.
3. Shut off the air to the pump.
4. Close the bleed-type master air valve (supplied
in your system).
5. Disengage the spray gun safety latch.
6. Hold a metal part of the spray gun firmly to the
side of a grounded metal pail, and trigger the
spray gun to relieve pressure.
7. Engage the spray gun safety latch.
8. Open the drain valve (supplied in your system),
having a container ready to catch the drainage.
9. Leave the drain valve 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, VERY
SLOWLY loosen the tip guard retaining nut or hose
end coupling and relieve pressure gradually, then
loosen completely. Now clear the tip or hose.
WARNING
WARNING
For your safety, before operating the equipment
be sure all operators have read and fully under-
stand all the warnings, cautions and instructions in
this manual and all manuals supplied with each
component or accessory.
Flush the Pump Before Using
Pumps are tested with lightweight oil which is left in to
protect the pump parts. To prevent contamination of the
fluid, flush the pump with a compatible solvent before us-
ing it.
WARNING
Before flushing, be sure the entire system and
flushing pails are properly grounded. Refer to
Grounding on page 3. Follow the Pressure Re-
lief Procedure Warning above, and
remove the
spray tip from the gun. Always use the lowest pos-
sible fluid pressure, and maintain firm metal-to-
metal contact between the gun and the pail during
flushing to reduce the risk of fluid injection, static
sparking, and splashing in the eyes or on the skin.
Starting and Adjusting the Pump
Be sure the air regulator and bleed-type master air valve
are closed.
DO NOT INSTALL THE SPRAY TIP YET!
Place the suction tube (21) in the fluid pail. Open the drain
valve (10) for priming. Open the bleed-type master air
valve. Hold a metal part of the spray gun firmly to the side
of a grounded metal pail and trigger the gun. Slowly open
the air regulator until the pump starts. Allow the pump to
cycle slowly until all the air is pushed out of the fluid lines.
Release the gun trigger and engage the safety latch; the
pump will stall against the pressure.
With the pump and lines primed, and with adequate air
pressure and volume supplied, the pump will start and
stop as the spray gun is triggered and released.
Follow the Pressure Relief Procedure Warning at left,
then install the spray tip in the gun.
Use the air regulator to control the pump speed and fluid
pressure. Always use the lowest pressure necessary to
achieve the desired results. Higher pressures waste fluid
and cause premature wear of the pump packings and
spray tip.
Keep the wet-cup filled with Graco Throat Seal Liquid
(TSL) to help prolong the packing life. Check the tight-
ness of the packing nut weekly. The packing nut should
be tight enough to prevent leakage – no tighter. Always
follow the Pressure Relief Procedure Warning at left
before adjusting the packing nut.
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, refill the supply
container and prime the pump and lines with fluid, being
sure to eliminate all air from the fluid system, or flush the
pump as described in “Shutdown and Care,” below.
Heated Systems
Operating instructions for a heated circulating system
are provided in the Viscon
Heater manual, 307-805.
Read and understand all warnings and instructions in the
heater manual before operating a heated system.
In circulating systems, adjust the back pressure regulator
(76) and pump air pressure regulator (28) to obtain prop-
er spray pressure at the gun and maintain sufficient circu-
lation flow to prevent fluid settling.
The three-way ball valve (70) selects either fluid circula-
tion or draining. To circulate fluid back to the pump, turn
the handle toward the CIRC end of the valve. To drain
fluid, turn the handle toward the DRAIN end.
Shutdown and Care
Always follow the Pressure Relief Procedure Warning
at left, whenever you shut off the pump. Stop the pump at
the bottom of its stroke to keep fluid from drying on the
exposed displacement rod and damaging throat pack-
ings.
Always flush the pump with a compatible solvent before
the fluid can dry on the displacement rod, and at the end
of each day. If you are pumping water-based fluid, flush
first with water and then with mineral spirits. If you are
pumping oil-based fluids, flush with mineral spirits only.
Relieve pressure and leave the mineral spirits in the
pump to prevent corrosion.
