Cool Cool Cool Thanks for that.Maybe this will help
I have ordered 11 and 14 , because one or the other has to be leaking. Hope I can get them.
But, seems to me if the front tank is empty that it would suck air from that direction ? Check valve in the vent as they call it, but the plastic fitting that goes in the tank hose?
And, the tank vent in the sump line is actually inside the tank. So, how is that supposed to work ?
Anyhow, I am going to replace it as built because it has been working for 40 years that way.
If that does not correct the issue I'll just declare too dumb to fix it.