I rebuilt the single action master cylinder on Volveeta when I cleaned it up and put it on the road the first time. I realized that there are many,many cars out there with the single setup but there is also a reason they all changed or required dual cylinders. I long ago decided that when I do a rebuild that would be one of the upgrades.
A couple things I needed to pay attention to – the center of the piston had to stay in the same place or it would be way too much fabrication for me,the brace that bolts to the engine side of the MC supports the shaft that the brake and clutch pedal pivot on and lastly the angle as mounted on the chassis had to stay the same otherwise it could bind or wear unusual.
I browsed the web looking at pictures of MCs and while doing so remembered the first duals that were used on some of the cars I owned,specifically Ford style. I liked the idea of having the fluid container and piston all in one. I also wanted the two brake lines coming off either the bottom or engine side of the unit. I found a few pics of the Ford units and they were close to what I wanted. I finally settled on one from a 1974 Mecury Cougar 5.8L. I ordered a remanufactured one from Autozone for $15.99 with an $8 core charge with tax and shipping it was $35.38 and arrived 4 days later.
I took a bunch of pics of the old setup for reference and also some measurements as to where the center of the piston should end up. I decided to put weld a plate about where the bracket bolt of the old one was. That would put the front of the piston in the same place. Then I calced the height and centerline and made the plate. There are pics below of the new setup in the process and finished. It turned out pretty good,or at least I think it is. The centerline is the same and I was able to use the old support brace with a bit of bending and drilling.
If you’re going to do one and have any questions,drop me a line. I also have a few more pics that I didn’t post from some other angles.
Here’s a couple pics of the single system (took these for my reference also):
FROM THE ENGINE SIDE
THE DRIVERS POSITION
AND FROM THE TOP.
The old one and the new one – It’s really bigger but there (I think I remember) is enough space in that area and the pistons are the same size,1″.
Measuring the angle.
Made the plate and ready to weld.
All welded in,support bracket adjusted and mount,now time to paint.