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[ftsoft]

Bicycle valves:

I liked the idea of this so I tried both a presta and a schraeder valve to see what was what. The presta didn't work at all ,the mity vac indicated that it would not hold negative pressure. I'm not sure why, as the tube that I took it out of was bad, but the valve seemed to work. anyway, the schraeder would hold negative pressure, although I couldn't blow through it very well. It DID work and the tube held air before I trashed it. So, where I started was with NO valve at all. Under this circumstance the lights come up right away but dip significantly as the engine is revved. inserting the schraeder valve into the system rendered everything inoperable. I tried it both ways. I don't know why this would be unless the valve needs more pressure than the engine generates to open. Anyone who has done this... could you chime in with what I might have done wrong? Also, Im assuming that my RH vacuum unit is bad since, as I mentioned, it needs to be lifted manually, whereas with the feed to the rh unit blocked, the lh unit comes up right away on its own. Thanks.

Frank