I have a 63 car FHC with a front brake hanging problem.
Car is fitted with a full series 2 brake system in front. It has the original dual MC system one circuit rear one front supported by the original bellow.
All brake system is new or overhauled. Apart from disconnected brake servo, where only coupe brass filter is replaced.
When car is cold one can push «one million» times. And all works good.
With a little driving, and engine is hot the front brakes start sticking more or less by itself. First I disconnected the vaccuum below from the brake MCs. That helped a little, then 500 yard driving and front brakes got really stuck.
Then I opened the bleeding nipple on one front caliper and car rolled again…
Then another 500- to 1000 yards and brakes were hanging again. Very little braking. Once or twice. Hand brake is very good on the car.
Then brakes were hanging again. Release pressure on bleed nipple front caliper again. And car rolling again.
My idea is here:
Heat cause liquid to expand. And faulty MC front brakes allthough completely new trap liquid in MC somehow.
Rear brakes work 100% ok, with and wo brake servo connected.