Bad Proportioning Valve?

[georides]

Hello there from New Jersey, USA

We were gifted a 1987 Supra Automatic non-turbo to resurrect, we've done a solid "tune-up", new starter, fluids, etc. problem now is the brakes.

On inspect the front pads were toast, while the rear pads were still thick, we got new rotors and pads in the front, and refinished the rears.

Did a line flush, but rear bleeders keep spitting out bubbles, pedal feels like air in the system until front pads engage (front calipers bled fine).

I would assume this is proportioning valve problem, we're going to disconnect it today and see if we can unscrew the valve on the bottom.

if our inspection cleaning makes no changes What would you think about just bypassing this valve with some new line splices?