Fitted a new master cylinder the other day on my 80 sport. The old one was shite and covered in corrosion. When i pulled it out there was a little plunger type thing sitting in the servo with a large washer that obviously pushes into the cylinder when the brakes are applied. It was just sitting inside the servo not seemingly attached to anything. In order to fit the new cylinder i had to remove it and place it into the new cylinder then gently slide the whole assembly into place through the large servo spring.
On reassembly, i seem to have no pressure and the foot brake goes right to the floor whith only some spring pressure to return it...

I started the engine thinking the servo might need "pumping up", but still nothing. The master cylinder is the correct part and looks identical to the one removed. What have i done wrong! I have no brakes.

I'll post some pics soon if i can.