Kevin, I tested it installed on the core only flowing one way. I will test it for flow the other way.

Bingo...... I reversed the flow putting the water to the valve first and it leaked like crazy. So now I have a choice to make. Send the valve off to be rebuilt by a professional or put in the readily available, much cheaper, standard heater core that doesn’t have a control valve in it.

Thanks to all those that helped.

Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
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