56 T Bird Brakes

G

GAR64

Senior Member
1956 TBird brake pedal was hard with little travel. I know the Midland booster doesn't do much but it seemed as though it was not functioning at all. Now the brakes will not release after a short run time. After a short time with car not running, they do release. I suspect a problem with the booster. Also need to replace master cylinder since I was unable to remove cap without busting it off. Anyhow, I am planning on going through all the brakes, new wheel cylinders, hoses etc. I read a little about these boosters and realize they are finicky. Looking for a place to send it for rebuilding. I don't want to convert to disc brakes but also do wonder if others have found an alternative to using this booster??? Appreciate any opinions.

greg
 
The Tbird parts suppliers (CASCO, Hill's and Prestige) can rebuild the booster.


Before you start ordering all sorts of parts, I would suggest looking at the parts you have. Things like wheel cylinder anyway,. If they are not leaking and are clean I would stay with what you got. As far as the master, replacement caps are available and I suggest the same as the wheel cylinders ( leaking, clean) before automatically replacing.


I think replacing all the rubber hoses is a good idea.
 
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Thanks Paul. Unfortunately, I busted the cap on the master and cannot remove it. I'll check into those suppliers as far as the booster is concerned.
 
A common problem is lack of a bit of end play in the pushrod between the brake pedal arm and master cylinder. Without some end play the master cylinder can't release the fluid pressure back into the reservoir.
Pressure builds and can lock the brakes.
 
Yes, its pretty new to me. My first thought was obviously to see if I lost fluid in the master cylinder but like I said, the cap snapped and I cannot remove. Doesn't look like I lost fluid at the wheels or hoses. Still had brakes, so likely there is still brake fluid. That booster is confusing to me. I'd like to replace the master cylinder and see if the problem persists but id like to try to get the old one opened up so I can check the status of fluid in the system. Looks like the boosters are quite expensive. Only drove the car a few times since i got it. Brake pedal always had very little travel and did not feel like power assist. It was just the last time i drove it that they locked up. Probably won't get out there to investigate further til weather warms up a bit.
 
Sounds to me like the inner hose, or the flexible hose(s) are rollling up inside when you step on the pedal.
 
If it were mine...and I have a '56 with a vacuum booster... I'd follow up on dmsfrr's suggestion in post #4 above and check the end play in the pushrod between the pedal mechanism and the master cylinder. Guessing someone before you did some "brake work" on your car. Also, CASCO sells a metal master cylinder cap after you remove the pieces of your old plastic one. Finally, I think I'm right about this but if not, someone will chime in to correct me. You need to bleed the booster first before moving to the right rear wheel. When I got my car two years ago, the brake fluid looked like mud puddle water and the fluid in the booster was the color of coffee!!! Brakes work very well now and I don't feel the need to convert to discs.

Best of luck with this, Greg. Keep us posted!!
 
You are correct. Bleed the booster first and then go to the cylinders


RKS.PA said:
If it were mine...and I have a '56 with a vacuum booster... I'd follow up on dmsfrr's suggestion in post #4 above and check the end play in the pushrod between the pedal mechanism and the master cylinder. Guessing someone before you did some "brake work" on your car. Also, CASCO sells a metal master cylinder cap after you remove the pieces of your old plastic one. Finally, I think I'm right about this but if not, someone will chime in to correct me. You need to bleed the booster first before moving to the right rear wheel. When I got my car two years ago, the brake fluid looked like mud puddle water and the fluid in the booster was the color of coffee!!! Brakes work very well now and I don't feel the need to convert to discs.

Best of luck with this, Greg. Keep us posted!!
Click to expand...
 
I had the experiences of too little clearance on the pedal rod. Didn’t completely lock the brakes, but close. I got off the road, and I had tools. A wrench on the line out of the master, with a rag around it produced a squirt of fluid obviously under pressure. I limped it to work (lots of room in front and lower gear on the hill). Re adjusted the pedal rod, problem gone. So it you find pressure there, it’s either the rod or the master. If not, it’s somewhere else. This is not to discourage you from going thru the brakes if required. Those OEM remote boosters don’t make nearly as much boost as modern ones, so I’d eliminate the locking problem (or isolate it to the booster) before I got my wallet out.
 
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If buying new replacement parts avoid anything made in china. Rubber pieces and seals seem to be made of substandard materials, similar to their defective-in-the-box new mechanical fuel pumps.

The master cylinder pushrod adjustment is an eccentric shouldered bolt holding the larger end of the pushrod to the brake pedal arm. Turning the bolt adjusts the end play. There is a locking nut on the threaded end that holds the bolt in place after adjustment.

There is usually a plastic tip on the small ribbed end of the pushrod. After several years it can crack apart or stick inside the master cylinder. This interferes with the end play and the pieces should be removed.

A couple example photos below.
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Thanks for the input. I'll investigate for sure before buying parts. What was said about the pushrod makes alot of sense.
 
If it’s locked, and you don’t get pressure at the master, check the master on the booster too. I don’t know that it would happen on one of those, but I chased a brake problem all last winter on a friends car. It had a small diameter vacumn booster, two diaphragms. We finally discovered the booster moved about 3/8” when the car was started (vacumn applied). It was putting the brakes on, and it didn’t retract when turned off of bled down. We called the supplier, told him what we’d seen and the immediate response was “one diaphragm failed. That’s what they do”. Rebuilt under warranty, worked,
 
miker98038 said:
If it’s locked, and you don’t get pressure at the master, check the master on the booster too. I don’t know that it would happen on one of those, but I chased a brake problem all last winter on a friends car. It had a small diameter vacumn booster, two diaphragms. We finally discovered the booster moved about 3/8” when the car was started (vacumn applied). It was putting the brakes on, and it didn’t retract when turned off of bled down. We called the supplier, told him what we’d seen and the immediate response was “one diaphragm failed. That’s what they do”. Rebuilt under warranty, worked,
Click to expand...

Now this is good information that will not be found in a manual.

I have a streetrod too, and it is amazing how you learn to investigate things, and re-engineer when you have a streetrod.
 
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