[Bearly Flying]

Actually Scott, after reading Jerry's post, I went back and tested the two actuators in their opposite positions, as per my photo's.

WVZR-1 and Jerry are correct, altho the linkage appears to be offset, it is pulling evenly on the diaphragm.

I shone a flashlight into the opening around the arm and watched while slowly increasing the vacuum, the diaphragm pulls evenly throughout the stroke.

I think what screws with your mind , is the arm moving across the face of the canister as it pulls back, but the distance between the diaphragm and the pivot does not change, therefore the angle will be consistent.

I think I will let sleeping dogs lay and keep the original orientation.

Thanks for all the insight and suggestions.

Don