breadrb,

"Keyswitch vacuum valve is open or in a loop? or closed" I don't know what the correct terminology is.

When I say vacuum is applied to the shut off valve I mean there is a continuous loop thru the keyswitch and vacuumn lines to the vacuum pump. A vacuum gage at the shutoff valve would give a reading.

If no vacuum was applied to the shut off valve, a gage would read zero.

P E H