Thanks for the info gents. I should have thought of my old Chevy with non-power brakes, my right leg got very strong pushing down on that pedal as it took all the pressure I had to stop it. Would the bad check valve leak brake fluid, or just allow air into the system? If there's brake fluid floating around somewhere I want to know where it would be so I can clean it up. Oh, and if anyone knows the proper procedure for bench-bleeding the master cyl. I could use some how-to. I'll let everyone know how it turns out, thanks again! -alan 83 320i 79 320i