This weekend I replaced the master cylinder on my 85 300sd.It was leaking internaly,causing the pedal to travel to the floor,but showing no signs of leaking.After installing the new master cylinder and bleeding the brakes,I took the car for a test drive.The brake booster is not working.Could I have made a mistake during installation?Could the booster have failed along with the m/c?I would be grateful for any help,ideas.