Hope this works. Love the forum, but hate the way adding pictures works!!!! unless I am doing it wrong.
Anyway, here are a few pics of the set up. Great autopilot when it works, so solid.
I agree that it might be air, I am now thinking it is an airlock in the system. There are no more leaks in the system, I have fixed them. One of the photos show a paper towel on the pump that has been there for a few weeks now to show leaks should there be any.