This is on my 69, with front disc brakes (power). I went to drive it today for the first time in several months and barely had a brake pedal. The rear brakes worked fine, in fact I could lock them up if i pushed the pedal down hard. No front brakes. I have no leaks. The master cylinder is full. The truck only has about 1300 miles on it since built. I don't think bleeding the front brakes would do any good, because there are no leaks, correct? Is my master cylinder bad you think?