Originally Posted by
LarrBeard
I'd look it over very closely before you decide to rebuild. DOT-3 brake fluid goes out and tries to find water to absorb into the system and then lets it sit at low places and corrode things. (It is very "hygroscopic"). The master cylinder is usually the low place in the system.
If there is any corrosion in the bore, you won't be able to get a good pedal.