Soft Peddle

I did a complete rebuild of the manual drum brakes on my 67 Dart GT. Wheel, and master cylinder, shoes, drums and rear line.

The rears bleed nice and clear with no air. When I bleed the front it runs clear for maybe 30 seconds and then starts running air bubbles. I have kept the master full and run at least 2 reservoirs of fluid and still get air.

I have tried the vacum, gravity and a pumper methods and still have little or no peddle. When I have another pump the peddle up it runs clear till the peddle hits the floor and then it starts pushing air?

I have checked all of the fittings, pulled drums and found no leaks.

I'm thinking I have a bad Master? It was a re-man