My 1970 v8 was bought as a restoration project and has been off the road for 32 years. I'm working through various jobs but the brakes have me scratching my head! The car has recon front and rear calipers, known good master cylinder, servo overhaul kit and new flexi hoses. I bled the brakes and ran the car up and down my drive yesterday but the brakes were sticking. Jacking it up confirmed that all four were sticking. Working from the master cylinder, releasing the unions had no effect until I loosened the servo to brass 4 way coupling Union on the inner wing. A good squirt of fluid when the union was released resulted in the brakes freeing off. Having had a similar issue with another p6, I suspected the air control valve piston to be at fault. So, off came the servo again. It was seized (forgot to check first time round) so I unseized it, cleaned the bore, renewed the piston rubber, checked for satisfactory movement and reassembled. I re bled the system today but they're still sticking on all four! I used the same Union releasing sequence as before and again, releasing the servo to 4 way coupling Union freed off the brakes. Have I still got a servo related fault? The only other explanation is that the 4 way coupling could be blocked after so many years laid up? Any suggestions greatly received!