More Brake problems!!!

[02stu]

Thanks for everyones help on the ABS problem. It turned out I didn't have the ABS pump powered correctly. However I still do not have very powerfull brakes at all. They are much worse then my 95 Suburban. Does this sound like a booster problem or could it still be the ABS pump? I am going to VIR in a month so I need to get this solved ASAP. Thanks again for your help, this one really has me stumped.

[Mike B.]

I don't recall, what booster are you running with your swap? What size master?

[02stu]

I am running a e21 320i booster

[Mike B.]

I had an e21 booster on one of my swaps with the stock master. I would describe the pedal feel as vague at best.

They performed adequately on the street and the track.

When you say underpowered, could you be a bit more specific with the feeling you have when you press the brakes?

[AndrewBird]

Stock master cylinder?

[e30evolution]

The brake master cylinder has an o ring on it that seals vacuum inside the booster.... if it is leaking there your brakes will suck

[02stu]

Stock master cylinder?

yep, stock.


The booster is holding vacuum, I took the hose off today to check the one way valve on the hose and the booster was still under vacuum with the car off.

[Massive Lee]

Hi 02stu

Are you using old pads on new discs (or vice-versa)? Did you change anything with the brakes? Did you open the lines to the air (bubbles)?

[submwar]

air bubbles will give you that inconsistent pedal feel
check out those seals they might be toast

[1990m3]

sounds like air in the line to me. I've also had problems with Hawk pads requiring me to pump the pedal one full time before any braking actually started to work. Switched out to different pads and the problem went away. I still don't get that one.

[emi325i]

sounds like air in the line to me. I've also had problems with Hawk pads requiring me to pump the pedal one full time before any braking actually started to work. Switched out to different pads and the problem went away. I still don't get that one.

Ha.. I knew I wasn't the only one that had problems with hawk pads. Those pads were scary no matter what car I put them on. I noticed they don't bite until warm. That makes for very scary winter driving.