brakes locking

[californiakid]

How can I diagnose why the brakes are locking up on a 1984 Volante? How to check servos? Master cylinder? Thanks in advance.

[californiakid]

I dismantled the master cylinder and found it to be in fine operating condition; someone had previously rebuilt it. The servo for the front brakes had a ruptured diaphragm and was obviously the cause of my brakes locking up; vacuum & brake fluid mixing. Will have both servos rebuilt.