My brake booster decided to die on me about a week ago. So i picked up a new one. This was the first time working with the brakes on my 260z, and i picked up some speed bleeders, they have worked really well for me in the past. Anyways, replacing the booster was no problem. But i have run into a problem with bleeding that i dont know how to explain, or at least explain without going and replacing a bunch of other brake components. I was able to bleed the front brakes just fine using the speed bleeders. But i have had issues with the back brakes. First off, when i tried to bleed the rear brakes, alot of rusty fluid came out, and then nothing came out, not even air, as if the line was clogged with rust or something, and i have no brake pressure. I traced my lines and checked connections for leaks, and checked if my bleeder had clogged and found nothing. And my the fluid levels in my master cylinder stay the same whenever i try to bleed the rear brakes. Im not an expert on automobiles, but am I going to have to replace my lines going to the rear brakes?