'59 Power brakes make a woosh sound when depressed

[Guest]

I'm just now getting around to putting this bird back on the road for the first time in 10 years. Yesterday, I bled the brakes using the buddy system and heard a wooshing sound when the pedal was depressed. I'm not too familiar with the brake set up on these. It looks like there is a piston below the master cylinder on the firewall that is going in and out making the noise. I have factory drums all the way around. That "woosh" sound normal? Or do I have a pressure leak somewhere?

[tbird430]

Sounds like a vacuum leak to me....

[jopizz]

Check the brake booster under the dash. It could be leaking or the vacuum hose that goes to it is leaking.

John

[KULTULZ]

http://www.autoshop101.com/forms/brake05.pdf

Scroll down to PG 17.