eurekax

have recently installed new power brake booster to my 72 which had manual brakes,i have connected the vacuum hose to the vac line which runs along the firewall,the one that feeds headlights etc.is this the right one or should I run a feed from back of the carby,the brakes stop the car well but the pedal seams to go to the floor slowly,i have bled the brakes twice [ I know they are a pain to bleed]and have no visible leaks anywhere,have rebuilt calipers and new brake hoses and new MC have checked vacuum at back of carby and is very strong. any ideas !!!! Thanks Alan

Danish Shark

On a 72 the brake booster it connected at the back of the carb base plate

gungatim

if the pedal slowly drifts to the floor after being held at a stop, you need a new master cylinder...they don't necessarily show signs of leaking when they can't hold pressure.

wcsinx

MC piston is bypassing ... nothing to do with the vacuum booster

mikem350

As Danish said, hook it to a dedicated vacuum source, like the 3/8 port on the carb or intake.

Then go from there

eurekax

Its a new Master cylinder,but will change vac source and see how it goes Thanks for the replies

7T1vette

You do not want to hook other vacuum lines in with the booster feed line. It NEEDS to be a dedicated source from a larger fitting.

eurekax

Will do thanks