Thanks for the suggestions, TBM

1. Water pump check - can I do that with the engine running and cold? That's what I did. There's not a whole lot of pressure or suction but it is flowing. I disconnected where it comes out of the heater first and the flow was less than when I checked the hose going in to the heater. The thermostat has been removed. I made a video recording of the result https://youtu.be/CQTs_J-ky5o

2. Will look into the air lock next.

Thanks again,

Brad

Last edited by BradB; 10/06/19 01:02 PM.