News:

Due to a technical issue, some recently uploaded pictures have been lost. We are investigating why this happened but the issue has been resolved so that future uploads should be safe.  You can also Modify your post (MORE...) and re-upload the pictures in your post.

Main Menu

1956 4dr Series 62 - BREAK sound

Started by Patrick Fant, June 13, 2020, 08:50:50 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Patrick Fant

Even with the engine off, I can step on the break pedal and hear a woosh sound like escaping pressure at the power break booster.  Was just rebuilt for treadle vac valve.  Is this unit still BAD or does it need to wear in for a while? pat fant CLC#31723
Patrick Fant
Houston
CLC #31723

J. Gomez

Quote from: pat@rfcmedia.com on June 13, 2020, 08:50:50 AM
Even with the engine off, I can step on the break pedal and hear a woosh sound like escaping pressure at the power break booster.  Was just rebuilt for treadle vac valve.  Is this unit still BAD or does it need to wear in for a while? pat fant CLC#31723

Pat,

Probably no, the sound you hear at the booster is probably the atmospheric pressure at the vacuum booster escaping from the air filter. That should be normal with no vacuum present at the booster or from the reserve canister.

There is also a valve at the power piston that allows atmospheric pressure to escape at the front with no vacuum present at the rear of the power piston. Since you are applying the brakes with no vacuum air pressure is built at the rear of the power piston (which holds the vacuum) so the valve releases the pressure.

Hope this helps..!
J. Gomez
CLC #23082

Patrick Fant

Great analysis J Gomez. Many thanks.  The old power booster was so quiet>  This rebuilt one squeals every time I press the pedal.  It stops great though.  Plenty of pressure.  Sounds like there is no "adjustment" on the power break system to try to dial that in, right?
Patrick Fant
Houston
CLC #31723

J. Gomez

Quote from: pat@rfcmedia.com on June 13, 2020, 04:24:38 PM
Great analysis J Gomez. Many thanks.  The old power booster was so quiet>  This rebuilt one squeals every time I press the pedal.  It stops great though.  Plenty of pressure.  Sounds like there is no "adjustment" on the power break system to try to dial that in, right?

Pat,

Unfortunately these units are all or nothing  ;)

Well that is a bit different  :o when you say "squeal" I hope the rebuilder lubricated the leather seal and the wick around it including the walls inside the booster where the leather travels. Placing these dry would cause the "squealing" sound you mention above as you have the leather rubbing against the booster wall.  ;)

Make sure to to reach out to them and double check.  ;)
J. Gomez
CLC #23082

Patrick Fant

That sounds like a definite possibility -- un-lubricated leather moving on the cylinder wall sounds right. thank you very much. pat
Patrick Fant
Houston
CLC #31723