Left brake goes to the floor. I supposedly had this repaired about 3 flights ago. Now the problem is back. It is a 79 Archer II with brakes on both sides and a "parking" brake below the panel. That means 5 master cylinders and two wheel cylinders and a couple of check valves. Anyone know where I can get a diagram of the brake system that might help. I have been told this is a common Piper problem - is it really?