DeTomaso Mailing List: February 2001, Message #105

First: pull a brake bleeder valve and have someone step (GENTLY!) on the 
pedal. If nothing comes out, the shuttle valve under the booster is stuck at 
one end of its travel blocking off the brakes in that end. If its the front, 
you have lost most of the brake capacity of the car... 
Second, If fluid does come out, then start pulling brake pads, then have 
someone step on the pedal and see how many operating pistons you have left in 
all the calipers. Its not uncommon to lose 1, 2 or even 4 pistons to 
stickiness in unserviced 30-yr-old calipers. Try this & let us know how it 
works out- J DeRyke