Firstfives.org

Here's the back story: I replaced the rusty front brake lines on a 530i with lines that were in good condition from another 530i. Replaced from MC to front calipers. I also replaced the rusty brake lines at the rear from the T junction above the Diff to the rear calipers. I installed a known to be good MC from the other car as well. I installed "speedbleeders" at every caliper to aid in bleeding. The issue is that I don't seem to be getting any brake fluid to the rear calipers when I open the bleeder 1/4 to 1/2 turn and pump the pedal? I went to the front calipers and tried to bleed them. Although there is fluid to the bleeders (I bled them in the order the manual says) the pedal does not become hard as you would think it gradually would and the level in the brake resevoir never seems to go down much?
The MC I put in was from a car that had very good brakes last time I used it about 6 months ago and I never had any issues with it before that. Do I need to disconnect the brake line from the MC to the rear brakes and try to blow compressed air thru the the brake line to see if there is a blockage?
What am I missing here?

Hallo
i have always very good results when using eazy bleed.

The rubber brake lines can swell and prevent fluid flow. I had that problem on a Bav years ago and no matter how hard I stood on the pedal I could only get a drop or two out. You wouldn't think it would block it so effectively given the pressure, but it can. Since air entered the system when you replaced the brake line, but you can't bleed it, a soft pedal makes sense, there's still air in there.

Karl,

I would highly recommend you get a pressure bleeder system like this https://youtu.be/-sF2aV5PE8Q. I've had my Motive Products bleeder for a long time now and I don't attempt brake bleeding jobs without it!

Plus, Motive sells different brake reservoir caps, or you can make one yourself with JB Weld, 3/8 to barb brass fitting, and a spare reservoir cap; I have a couple customs in my collection (as home-made is typically cheaper).

The benefit of this system is that once it's pressurized, you can go around and inspect any swollen hoses, etc., since the system has pressure. I have no doubt you will find your answer with a pressure bleeder.

Mike

It turns out that I had one of the front brake line hoses installed wrong. Fixed that.
The other issue was that air was bleeding by a couple of the one way speed bleeders! Never seen that before? Perhaps the bleeder holes in the caliper were slightly worn or the sealant on the speed bleeder threads wasn't good enough? I swapped in a couple of spare bleeders I had and they sealed and problem solved.