one thing to check, drain the coolant down so you can see the tops of the core and shine a light in and see if the tubes are clear. when you flushed the engine you may have loosened something and plugged the core.
Ron, The Computer Greek I love therefore I am. 1954 3100 Chevy truck In the Gallery 2017 Buick Encore See more pix 1960 MGA Roadster Sold 7/18/2017