question on master cylinder.

[willowbilly3]

I mounted a 62 era Galaxy master cylinder to a 7 inch dual diaphragm booster on an of topic car. (Ok to replace the treadle-vac on my 56 caddy). Final went to move the car and the pedal was rock hard. I have good vacuum. I pulled the m/c and the booster moves ok. Pulled the m/c and it pumped fine. Re-installed it and tried it with the line off (engine running) and everything seemed ok, had boost and pumped out fluid. No blockage in system, all new and gravity bled fine.
Now the question is, does it matter which port you plumb the brakes to? I used the top one where the brake light switch would normally go.

[rich b]

If you are using the Treadle-Vac pedal assy, you probably do not have enough mechanical advantage to push a regular booster and master.

[Motorhead6]

I assume that is a single line M/C. In that case it does not matter which port you use as I believe they intersect to the main line of fluid flow anyway.

[willowbilly3]

Originally Posted by Motorhead6

I assume that is a single line M/C. In that case it does not matter which port you use as I believe they intersect to the main line of fluid flow anyway.

That's what I thought.
And I'll have to check the pedal ratio on the bell crank, never thought of that.

[willowbilly3]

I just took a flashlight and had a look. I think rich nailed it. Looks like barely 2:1 pedal ratio. I'll have to rework some of the pivot points from the pedal to the bell crank.

[tdlmomowers]

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Make sure that you have some free play in the master cylinder rod.

[willowbilly3]

The master cyl really doesn't have a rod, just bolts right on the booster. Maybe some small adjustment on the stub coming out of the booster.
And thanks for helping me on my non ford, 2 caddy forums and nobody knew there was no pedal ratio??