Originally Posted by Crusty
In the W-C head that you have, the two pumps have been replaced with one pump for both functions... That's why it's possible to get fresh water contamination with that head since it was designed to use sea water for flushing rather than potable water.
I Gotcha - yes, that's what I was trying to say, but butchered it. I have no interest in adding a separate water supply, incorporating a backflow preventer so we don't get waste in the fresh tank, or any other options to try and reinvent this head.
It's on eBay and will hopefully find a happy home in a charming old boat... right where it belongs.