I had a brake fluid leak on my new (to me) 86 635 and I followed the terrific article in Norm Grills website about how to do it (big coupe group).I thought I followed it to a Tee.
I refilled the brake fluid reservoir and the PS fluid reservoir with tranny fluid.Cleaned it all up and pumped the brake pedal and got no resistance after 20 pumps or so.Heard screeching sound and found my
brake fluid reservoir was empty.Filled it again and started pumping, same thing.I have a slight leak at the rectangular hole at the bottom of the booster but not bad enough to drain the 2 qts of tranny fluid that I have lost.As I now have a toxic puddle of kitty litter and trans fluid on my garage floor I need to call for help.

1. I got a new 3x38 mm O ring and installed it correctly, why is it leaking?
2. Brake fluid connections are not cross threaded, I "worried" them in by hand and then tightened them with a wrench.
3. Where's all the tranny fluid going, there's only a rubber hose and a fitting that I tightened OK.

I can't get underneath until the sludge dries out, should I dismantle everything again, my brake fluid level hasn't changed.I just get a sqeaking sound but no back pressure at all when I pump the pedal.

Where did I go wrong?

I'll remember somebody in my will!

Jim C