54 chevy brake problems

Hey guys,
I'm new here,
I have a 54 chevy and have had to pump the brakes for some time now. I rebuilt all the cylinders and the master about a year ago and it had no improvement. So, last week a finally bought a new master cylinder, after I promised myself I would never do it, and still.........the first time the pedal goes down it does nothing, second, it is better and third- hard as a rock. While holding in, it doesn't go down. But, once I let up, and push in again, it goes tothe floor. any ideas? Also, I have blead them a bunch...

thanks again

 

I assume you have stock brakes? Have you adjusted them?

 

Not another Chevy brake prob !! LOL First are all the brakes adjusted correctly. Second does the push rod to the M/C have a little free play in it when the brakes are released? The symtoms you are discribing are classic for brake way out of adjustment. What contion are the shoes and drums in?

 

In what sequince have you blead them? Did you bleed the rear before you bleed the front?

 

hey guys thanks for the replies,
i believe they are adjusted correctly.
I moved the adjuster so they dont rub; i even adjusted so that the shoes
do hit just a bit, just to see if that had an impact. It didn't.
I'm not sure about the free play, but I will check tomorrow and get back
with you. Also, I have blead the brakes front back back front and then again a few billion times.
thanks for the input.
I'll let you know about the push rod play

 

If the drums are out of round you will never get them adjusted properlly.On brakes with out self adjusters,which yours are, you tighten adjuster until you cannot turn wheel and then back off till it turns free.

 

Exactly what sdluck said. If you adjusted as per your reply that is a major part of the issue. One quick check is to apply the e-brake and check the brakes. The pedal should be better... a clear sign of brakes that need adjustment.