New Master Cylinder Leaking at the boster?

[daveybtv]

Is it bad or did I do something wrong?

[Apogee]

Brand new installation or is this a used unit that's been in service for a while? Generally speaking, if/when they leak fluid from the piston end, it's time to rebuild or replace the unit. That said, I've also seen new and used units weep a small amount of fluid during bleeding that ended up bench bleeding fine and then running for years, so a little more info might be helpful.

Tobin
KORE3

[daveybtv]

IT was a new one, Cheep from Advanced auto I did not bench bleed it So I went and got another one. This time I bench bleed it just put it on so far so good. Now I have to re-bleed the system and hopefully this will fix it.

[woody80z28]

I just had this happen with a brand new ACDelco master in my Beretta. Didnt notice anything when I bench bled it, but it was leaking out the booster. I replaced the master and all is fine except now when I'm on the brakes I can hear a vacuum leak and the idle pick up. So keep an eye on it and make sure your booster didn't get wrecked by the leaky master. I gotta grab a new booster to put in it.