W110 Brakes not working and I知 frustrated

[WillemKlunder]

I知 very frustrated with my braking system. Since acquiring the vehicle I致e done a number of things to the braking system over the winter. I was having trouble stopping the vehicle in the first place. All friction components i.e. (pads, shoes, and rotors) have been replaced. Ive also replaced one front calliper, and both rear wheel cylinders. I also had to replace one of the rear flex lines. During my diagnostic process I installed a new master cylinder as well as a precautionary measure.

After installing all these components and bleeding the brake system the issue did not go away. It actually almost seems worse. The only way to stop the car is by the hand brake.

The brake pedal feels spongy but also is very hard to press. When you press hard enough the pedal goes to the floor. I jacked up the driver side front wheel and spun it by hand. I got my father to press the pedal as I turned it. He pressed it to the floor and the wheel instantly locked up but then it seems to loose braking pressure as the wheel then becomes free again while the pedal is still on the floor.

My only thinking now is to get the brake booster repaired however this is not cheap as some of you may know.

If anyone can help please do. Thank you