I have a dual system, originally got a leak in rear wheel cylinder, replaced all 4 with brand new now I'm bleeding the rear drums. I have blead them until there is no air, still soft pedal, blead again just to be sure, still soft pedal. I have not "set up my drums" ie: adjusted my wheel cylinders yet.... could that be the issue? I've put over 1 L of fluid through the system still soft pedal.... any advice is appreciated.