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Brake Master Cylinder Rebuild

Camshaft

Jedi Knight
Offline
My worst fears have materialized, and my 1978 Midget's brake master cylinder has finally given up the ghost. Specifically, the rubber seal, which has rotted away from years of American brake fluid. How difficult is it to rebuild the system with a new seal?
 
There is a snap ring deep in the bore that you have to carefully extract. One false move and it'll score the bore, and then you might have to do a rehone, too. I was too chicken to try it myself, so I had it done for me. My understanding is that other than that snap ring it's a piece o'cake.
 
Thanks for that bit of info. Are there any good how-tos or tutorials out there? I haven't had any luck finding any.
 
here are my instructions - it is not a difficult job and compared to buying new is worth trying. If it doesn't work, you're still only out a few $

https://tinyurl.com/9q8nl9
 
Apple Hydrolics and White Post do master cylinder rebuilds that will last 100 years.
 
Okay gentlemen, I got my rebuild kit today, and the cylinder is *almost* out. I say almost because one of the brake lines unscrewed about 3/4 of the way and just spins, now. It may be stripped. Any suggestions?
 
any way you can put a screwdriver on the flange of the line and apply outward pressure as you turn it - if you're pushing and turning, you should hopefully get it the rest of the way
 
When the nut is tightened the flare may grow in diameter. You have loosened the nut all of the way and it is clear of the threads in the master cylinder. You now have to pull the flare/tubing past the threads. Do as JPSmit said. Pull and shake the tubing from side to side. This is common.
 
I did this repair not to long ago. Spend the money on a good long nose snap ring tool it will help immensly in the rebuild process. Otherwise the only other problem I had was getting the plastic bushing thing out when I did the rebuild. I couldn't find any other way to get it lose other than to melt it a bit with a small torch and jab it with a small screw driver and pull the half melted bushing out. The kit I had had a replacement bushing so I wasn't really concerned with saving the old one.
 
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