[Mark66]

I bought a 66 convertible that has sat for a couple of years but is in overall good running condition. The problem is that the front and rear brakes were completely redone within the last 3 years-including the power brake booster and master cylinder. The brakes do work. However, at a certain point they grab and as I press through the spot the braking action returns to normal. Are the power boosters notoriously bad on these babies? What else might the problem be? The booster assembly has less than 3700 miles on it. Thanks!