1956 olds 88 power brakes problem - need help

[neilvw]

Besides my Reatta I also have a 1956 Olds 88 in which when I fire it up the brakes work fine and then after getting it on the road and a few light braking events the pedal and brakes start getting mushy until actually one time the pedal went to the floor and brakes would not work at all....I have checked fluid level and it is 1/2 above bottom of dipstick which I think is fine but there are no marks on dipstick to indicate good or bad...I also have no leaks at any brake line or brake cylinder or from unit itself...I also removed the vacuum valve and the thru line is clear but the "T" line that goes to carb is slightly clogged and has no "check valve" type function whatsoever....Because the brakes work fine upon startup I am scratching my head on why after time, heat and brake cycling the brakes start to fail..... soooooo...I think sending unit out for pricey rebuild may not fix this problem!!!!.....

Edited Monday at 09:15 PM by neilvw
fix error (see edit history)