Hi everyone, just bought myself an E30 320i, love it but it has a very bad brake problem.
If you "drag" the brakes upto traffic lights or roundabouts they don't work but if you push hard on the pedal they work properly.
The guy I bought it from said its the master cylinder?
Just wondering is this true and how much it'll be to fix, this is my first BMW so into a new world of parts and fixing stuff lol.
New E30 owner. Brake problem
Moderator: martauto
- check condition of brake fluid in the reservoir, it might be obviously dirty and old in which case flush the whole system
- check the fluid that comes out of each caliper as you bleed the brakes, it might still be dirty or old even though what is in the reservoir looks OK
- bleed each caliper, make sure there is no air in the lines
- flush the whole thing. Buy enough brake fluid of a different color to make replacement obvious when the new fluid starts coming out, bleed it through the system so all is replaced. If you just bought the car it's probably a good idea, should be done at least every couple of years.
I don't know how to diagnose a master cylinder problem but if the seller said that was it, maybe he does and I don't know why anyone would tell you it's the expensive bit if they weren't sure.
If you do need to replace it then it might be worth considering fitting the 7-series master cylinder, bolt-on compatible* but larger diameter, you get more force for less pedal travel.
*depending on your exact model and year you may need a T-adapter also, not expensive.
- check the fluid that comes out of each caliper as you bleed the brakes, it might still be dirty or old even though what is in the reservoir looks OK
- bleed each caliper, make sure there is no air in the lines
- flush the whole thing. Buy enough brake fluid of a different color to make replacement obvious when the new fluid starts coming out, bleed it through the system so all is replaced. If you just bought the car it's probably a good idea, should be done at least every couple of years.
I don't know how to diagnose a master cylinder problem but if the seller said that was it, maybe he does and I don't know why anyone would tell you it's the expensive bit if they weren't sure.
If you do need to replace it then it might be worth considering fitting the 7-series master cylinder, bolt-on compatible* but larger diameter, you get more force for less pedal travel.
*depending on your exact model and year you may need a T-adapter also, not expensive.
Ok thanks. I think it's more than just bleeding because you press the brakes and they bring you to a stop. If u keep your foot down on the pedal the brakes stop working and you have to reapply them or use the handbrake.
It's a 1988 F reg 320i saloon.
It's a 1988 F reg 320i saloon.

