Bleeding Brakes

[Roadhammer]

Searched a little and didnt find anyine with the same issue.

Im trying to bleed my newly run brakes. 1979 disks and crossmember in front and old drums in back. 1979 dual master cylinder up front.

Ive had success in the back both old rusty valves opened and allow brake fluid to exit and even squirt out so they work, but the front valves were full of rust so i cleaned them out so they could breath and they still wont let any fluid come out. as far as i can tell i have had no fluid leave the front cylinder resevior at all. Dont know why this would be. I installed all new lines for the front brakes(used old hoses but they worked fine before i drove the 1979 600 miles home with those brakelines.

The only think i can think of is that the proportioning valve might be cutting off the flow but i only have a ver limitted knowledge of how those work.

any ideas?

Jory