Brake problem Question????

Edited: 8/25/2009 12:12:18 PM by bagged85

 Hello I have a 93 chevy s10. the brake lines rusted through. I replaced all the lines. I blead the brakes. I have fluid comming out of all four cylinders with no air. But my brake pedal still has very little pressure and doesnt return up very quickly. could the master cylinder be bad? Im not loosing fluid in the resivor and there are no leaks under truck.
Thanks, Scott

it could be bleeding the fluid through the seal on the piston inside of the master cylinder.  which would mean recplacing the master cylinder

sounds like an internal bypass failure.first with the car off pump the pedal and hold you want to see if its drops down while holding pressure if it does you need a new master. if pressure is steady hold and start truck to see if you have a drop in pedal shows wheather or not your booster is good. after all that is done hold pressure on pedal and turn off truck you want to feel for the pedal to rise if it does master is good.  This is all for stock braking if you upgraded anything let me know I'll diagnose it for you. I do brakes for a living so if anyone has a ???? i'll answer it.