I have a 1st gen. 1979. The right front brake only is locking up. Canged everything from the caliper to the master cylinder. Still locking. I can bleed it at the master and it works well for a little while. Is there any way to find out if I bought a bad master.

 

ya buy another one put it on...if it works put the other one in the box...take it back say you put it on and tested it out but for some unknown reason it doesn't work...then get your money back

 

Gee Lee, I thought this was an automotive help forum, not Thieves-R-Us.

Sounds like the cup for the left front brake, inside the master cylinder is bypassing fluid. If the brake lines to the left front isn't blocked, time for a new master. Be sure to bench bleed before install.