Firstfives.org

Bavauto has a special tool for bleeding the clutch slave as apparently air can get trapped inside after normal bleeding because of where the bleeder is mounted. Has anyone come up with a DIY method to bleed the slave to avoid buying the tool?

Yep, bleeding BMW clutches is odd. There's a number of techniques, the one I use is to unbolt it and pull it off with the line still attached. Then pump it by pushing in the pushrod on the slave several times. Do not open the bleeder while doing this, and pump the slave cylinder, not the pedal. Then reattach. You should have some pedal, even if not much. At that point pump the clutch pedal, you might have to do it by hand as it can get stuck and not return. But pump it maybe 10, 20, even 50 or 100 times and the pedal will come up.

Note, at no point did I ever open the bleeder screw. Odd, but it works. I think it's because it's self adjusting, but all I really know is it works.

The best method I've found for this is to pump fluid through the bleeder on the slave back up through the line ultimately filling the reservoir from the bottom. I did that on one of my E28s and got a perfect pedal right away. If you don't have a pressure bleeder it's the way to go. All you need is an oil can and a length of tubing to go from the spout onto the bleeder.