Technical "57 Buick Master cylinder removal

I am working on a friends '57 Buick. I am waking it up after a 35 year indoor sleep, so that he can selling. It's only has 56040 original miles on it. Needs a windshield, that is why it sat for 35 yrs.

How the heck do I remove the master cylinder. I removed the 4 bolts that bolt the plate to the master to the body, but it won't give it up. It's solid. What do I need to do to remove it?

Thanks, Pat

 

Have you given it a good persuasion with a good hammer? That won't hurt it. It could just be stuck to the firewall.
That car is a beauty.

 

The master has bolts coming from inside of a plate it bolts to, and I removed the bolts that hold the plate to a large box type thing, which is bolted to the firewall. It is still solid. I tried to pry it loose, but no go. I don't want to wreck anything getting it off.

 

Can you remove the box?

 

The end of the cylinder that sticks through the inside of the firewall has a large nut on it. There was a special tool for removal., however a modern solution is to practice yoga for a couple of hours, position your self upside down under the dash (stand on your head) and with a large pair of channel locks and a lot of patience you will be able to remove. They are a genuine pain in the a** to remove! Good luck!

 

It sounds like taking the seat out would be worth the trouble.

 

Hmm, when I looked (I will check again) I didn't see anything, but a hole the push rod went through on the inside. The back of the master base is a good 6-7 inches out from the firewall. The master has 3 bolts holding it from the inside of a plate, the plate is bolted from the outside with 4 bolts. Look in the picture, you can see what I'm saying.

Thanks, Pat

 

Might be! I never took the time/made the effort to do that! There is zero clearance so it takes lots of short turns to get the nut backed off. Also disconnect the cylinder rod from the brake pedal. Even more fun to replace!

 

Just sayin, I have a couple of 57’s and have been through the agony more than once!

 

In the future they'll have mini-robots to do that stuff.

 

Well, it doesn't sound fun of co****! I'm on my way there now to recheck it out. Still think it comes off out side. But, I'm not forsure yet. I will know soon.................................Hopefully! lol

 

I'm not sure if you understood g3. I think he meant that there is a large nut inside that has to come off before it will come out from the outside.
PS: Well, it sounds like fun from this end.

WD40. Lots of WD40. And as aforementioned, patience, lots of it.

Interesting note-
N.A.S.A. was trying to develope a water displacent. It took 40 tries to get it. (That's patience) So, WD 40 stands for Water Displacent, 40th formula.

 

BoogittyShoe is correct. Nut is on the inside of the firewall. Just guessing but think the OD of the threaded portion of the master cylinder is probably 1 1/2” to 1 3/4”. Big Nut!

 

Progress?

 

I thank you all, we decided to try just bleeding it, instead of just changing it out. It did bleed, and seems to be holding strong pressure. So we will drive it around today and go from there. Like you guys been say, there's a big nut on the inside, and it looks like taking the complete brake system out, piece by piece would be the easiest to unhook the rod, and to remove the nut!

Thanks, again! Pat