Start And Adjust Pump; Change Drums - Graco L20c Operation

L20c Supply Systems

Start and Adjust Pump

Keep hands and fingers away from the priming piston
during operation and whenever the pump is charged
with air. Follow Pressure Relief Procedure before
checking, clearing, or cleaning the priming piston.
1. Supply fluid to the pump, per the requirements of
your system.
2. Close the air motor valve. Set the director valve to
DOWN.
3. Reduce the air motor regulator pressure and open
the air motor shutoff valve.
4. Adjust air motor regulator until the pump starts.
5. Cycle the pump slowly until all air is pushed out and
the pump and hoses are fully primed.
6. Release the gun/valve trigger and lock the trigger
safety. The pump should stall against pressure.
To reduce the risk of fluid injection, do not use your
hand or fingers to cover the bleed hole on the under-
side of the bleed valve body when priming the pump.
Use the handle or a crescent wrench to open and close
the bleed plug.
7. If the pump fails to prime properly, open the pump
bleed valve slightly. Use the bleed hole, on the
underside of the valve, as a priming valve until the
fluid appears at the hole. Close the plug.
Always use lowest possible fluid pressure to bleed
air out of pump.
8. With the pump and lines primed, and with adequate
air pressure and volume supplied, the pump will
start and stop as you open and close the gun/valve.
In a circulating system, the pump will speed up or
slow down on demand, until the air supply is shut
off.
9. Use the air motor regulator to control the pump
speed and the fluid pressure. Always use the lowest
air pressure necessary to get the desired results.
Higher pressures cause premature tip/nozzle and
pump wear.
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Change Drums

1. Turn the air motor valve off to stop the pump.
2. Set elevator director valve to UP to raise the platen
and immediately press and hold the blowoff air but-
ton until the platen is completely out of drum. Use
minimum amount of air pressure necessary to push
the platen out of the drum.
Excessive air pressure in the material drum could
cause the drum to rupture, causing serious injury.
The platen must be free to move out of the drum.
Never use drum blowoff air with a damaged drum.
3. Release the blowoff air button and allow the ram to
rise to its full height.
4. Remove empty drum.
5. Inspect platen and, if necessary, remove any
remaining material or material build–up.
6. Go to Step 4 of Start and Adjust Ram.