I just finished an SAS on my '86 4Runner which included new FJ40 Rotors, rebuilt 1990 V6 calipers and new extended brake lines. Previously I had updated the '86 M/C and vac. booster to ones from a wrecker out of a '91 4Runner.

My issue is that the pedal travels about two-thirds of the way down before I feel any braking. We've bled the system in FSM order a couple of times and the fluid is fresh. After bleeding the pedal feels firm but when I start the motor it goes soft again.

Does this sound like a M/C issue? Would my brakes behave the same way if the M/C was fine but just needed bench bleeding?

Thanks for reading this long-winded post!

Warren