Well, my brake swap was just completed yesterday and along with that went the 1" itr master cylinder and the corresponding brake booster. Everything seemed fine and the lines were bled pretty well. We didn't notice we had a problem until the car was taken out for a drive and returned. It seems that there is a vacuum leak in the booster between the master cylinder and the booster. This is causing a loud hissing noise whenever the car is on. Also, the brakes aren't very compliant but do work. There isn't a problem with a surging idle or anything. Now my question is, is the problem originating from the booster itself because it's not holding vacuum or is there a problem with the seal between the master cylinder and the booster? Any suggestions would be appreciated. TIA

 

Not sure, but I think the seal would be easiest to test. If you can get a peak at it with the car on you should be able to find the leak.

 

Oops, sorry I forgot to mention that we are pretty sure the leak is at the bottom of the m/c and booster mounting area.

 

anyone? anyone?

 

sup soundbomber. i hate it when we put in all the work to have **** fail. good luck on getting the part and let us know.

 

word "eck fore" ******* i got my alignment done today, and the rear is off. I suspect bent rear trailing arms. Anyways, we're gonna try and use the drum trailing arms. And the booster is BANK brand new.

 

Try applying the brakes with the car no moving....if the pedal continues to move downwards slowly after you have hit the "stop" point, that means your booster is not holding pressure and is leaking.

 

nah, i don't have that kind of problem. The brake pedal stops at that stop point

 

its a leak around the seal where the MC bolts to it. i have the same problem. the booser is probably slightly bent around that area. try flattening it and putting some liquid gasket on it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rewsnaeht &raquo;</TD></TR><TR><TD CLASS="quote">its a leak around the seal where the MC bolts to it. i have the same problem. the booser is probably slightly bent around that area. try flattening it and putting some liquid gasket on it.</TD></TR></TABLE>

HELL YEAH! Cheers. Thanks man. I knew i cruise this board all day for a reason. Any suggestions as to what to seal it with? silicone or something?