A CHECK VALVE HERE WILL OPEN ON SWITCH OFF WHEN THE PRESSURE DROPS

O2 SENSOR

MANIFOLD PRESSURETHROTTLE POSITION FEED BACK

1ST BUBBLER

2ND BUBBLER/ SCRUBBER/ FLASH BACK PREVENTER

AIR INTAKE

SCHEMATIC TO SHOW HOW A CHECK VALVE CAN BE USED TO PREVENT THE DRAW BACK OF THE WATER FROM THE FIRST BUBBLER. JIM O'DONNELL (AVIATAKL) 2008