Brake master cylinder leak

[zachattack_5491]

I just replaced my brake master cylinder yesterday to fix my old leaky one. Is there supposed to be a gasket in-between the master and the booster? It sounds like there's just some massive air leak somewhere. when I turn my car off it sounds like a vacuum coming from that area for about 3-5 seconds. So I just need to know if I can put some liquid gasket on there to fix that.

[vancouverbc]

I just replaced my brake master cylinder yesterday to fix my old leaky one. Is there supposed to be a gasket in-between the master and the booster? It sounds like there's just some massive air leak somewhere. when I turn my car off it sounds like a vacuum coming from that area for about 3-5 seconds. So I just need to know if I can put some liquid gasket on there to fix that.

i

Not that I recall on my 1991.

[vancouverbc]

zerothread?id=250166

[unibody_s13]

I just replaced my brake master cylinder yesterday to fix my old leaky one. Is there supposed to be a gasket in-between the master and the booster? It sounds like there's just some massive air leak somewhere. when I turn my car off it sounds like a vacuum coming from that area for about 3-5 seconds. So I just need to know if I can put some liquid gasket on there to fix that.

no gasket... did u tried to bleed the brake mc before u installed it back???

[zachattack_5491]

Yeah, I bench bled the MC before I put it back on. And made sure no air entered the lines. Is it possible that I got fluid in my booster? And it's still just sort of dripping out slowly?

I guess that weird sound after i turn my car off must be something else.

[vancouverbc]

Yeah, I bench bled the MC before I put it back on. And made sure no air entered the lines. Is it possible that I got fluid in my booster? And it's still just sort of dripping out slowly?

I guess that weird sound after i turn my car off must be something else.

you prolly never listened carefully before.

[unibody_s13]

Yeah, I bench bled the MC before I put it back on. And made sure no air entered the lines. Is it possible that I got fluid in my booster? And it's still just sort of dripping out slowly?

I guess that weird sound after i turn my car off must be something else.

have u torqued ur mc right? and also the mc lines? its hard to get fluid inside the booster...

try driving ur car again for a couple of miles and check if that sound is stil der...

[zachattack_5491]

you prolly never listened carefully before.

well no... that sound has always been there. I remember hearing it hours after I bought my car. I just thought by putting in a new MC that would fix all of life's problems. Just wanted to make sure I wasn't doing something obviously wrong. Oh well... my quest continues.

have u torqued ur mc right? and also the mc lines? its hard to get fluid inside the booster...

try driving ur car again for a couple of miles and check if that sound is stil der...

You know what... I didn't torque it down. I forgot because it started snowing on me. It's still tight, but probably not to the right torque specs.

[unibody_s13]

well no... that sound has always been there. I remember hearing it hours after I bought my car. I just thought by putting in a new MC that would fix all of life's problems. Just wanted to make sure I wasn't doing something obviously wrong. Oh well... my quest continues.

You know what... I didn't torque it down. I forgot because it started snowing on me. It's still tight, but probably not to the right torque specs.

if thats the case u need to check everything... at least mc's okay... 1 down ... try checking parts that are air(line) related... or try check ur gaskets or holes on ur exhaust manifold all the way to ur exhaust...

[zachattack_5491]

Alright cool! Well I'm gonna go brave the blizzard right now to put my door panels back on. And I'll go try to do a hardcore inspection first thing tomorrow. (Probably around the crack of noon lol)

[zachattack_5491]

Ah... I can't find anything. I can't fit my head down there far enough to find this weird air leak. Oh well... as long as I know that it's not the mc that's the problem. I'll find it eventually. Thanks!

[onosqv]

If there is air coming out of that area, the brake booster is busted/starting to die.

Try this. After your car is already off, pump the brake a few times - the last time holding it down. If it stays stiff, then you are okay & what you heard may be coming from somewhere else (there's a lot of stuff on that driver side if you are all stock).

If the pedal depresses down to the floor or has that "spongy" feeling, then the brake booster is not holding the vacuum. This happened to me before, and sounds like your issue from the information you provided.

[zachattack_5491]

I'll try that in the morning. But I was warming up my car one time and that air leak noise was really loud. It sounded like it was coming from inside the car. But I just didn't think much of it. Then I pressed my brakes to take off and the noise stopped. Let go and it started again so I was like

I damn sure hope it's not my booster. That's going to hinder my q45 brake upgrade budget.

[unibody_s13]

I'll try that in the morning. But I was warming up my car one time and that air leak noise was really loud. It sounded like it was coming from inside the car. But I just didn't think much of it. Then I pressed my brakes to take off and the noise stopped. Let go and it started again so I was like

I damn sure hope it's not my booster. That's going to hinder my q45 brake upgrade budget.

if ur going to change ur booster go get the ones for the auto with abs... bigger and better!!!

[zachattack_5491]

if ur going to change ur booster go get the ones for the auto with abs... bigger and better!!!

Alright, well I'd prefer to not have to get a new booster. But that's good to know! Would that be better for q45 brakes or is there some other upgrade that would be better for those? I guess that's my new project... brake system. I've just been upgrading everything as it breaks. It's a kickass method.

[unibody_s13]

Alright, well I'd prefer to not have to get a new booster. But that's good to know! Would that be better for q45 brakes or is there some other upgrade that would be better for those? I guess that's my new project... brake system. I've just been upgrading everything as it breaks. It's a kickass method.

i prefer z32 30mm brakes... the z32 rear takes time to do but its worth it!!!

[zachattack_5491]

Yeah, I thought about doing z32s but I just can't spend that much money. I'd have to buy new calipers because there's not a single junk yard around here that has a sports car. And those bad boys are expensive. So I was kinda just planning on doing the q45 because that just appeals to me more for some reason.

Plus I know where I can get the rotors pre-drilled for 4 lugs

[Vedoman]

i have that same problem with that air leak sound around the booster so i took off the vac hose and pluged it, when i started the car again to test it the sound was gone. im pretty sure the booster is bad. o and it also causes a vacuum drop when i push on the brakes.

[zachattack_5491]

yeah, well thats prob what the problem is then. because when i press the brakes my rpms dip to 500. I'm guessing that's just from the disruption in the vac system. damnit

[vancouverbc]

yeah, well thats prob what the problem is then. because when i press the brakes my rpms dip to 500. I'm guessing that's just from the disruption in the vac system. damnit

the rpm should drop 50-100 rpm for normal car. no idea why.

[zachattack_5491]

oh really? alright.... well I'll go do some further inspections lol. This is only taking me in circles. haha