We brought a 1965 250SE Coupe back to life after a 20 year hibernation. We worked thru the car and recovered the injection, engine, transmission, interior. The only thing that was a bit problematic are the brakes. The calipers and rotors are fine, the car braked okay, but without power brake. The rear pressure regulator was cleaned and new seals fit, a new master cylinder and a rebuilt vacuum assist put in place. So now the power brakes work well...for a while. Repeated application results in the brakes gradually failing to release and binding up the rotors. Wait a while and they return to normal. The obvious problem is the vacuum assist unit; the brakes work fine with the assist disconnected from the manifold.
But what can be taking place in the boost unit that holds the brakes on? I can't find a drawing that shows the valving inside the boost unit to figure it out. Does anyone know?
But what can be taking place in the boost unit that holds the brakes on? I can't find a drawing that shows the valving inside the boost unit to figure it out. Does anyone know?
