Hi Lizem,The 124 manual states to drain the master cylinder down to about 10mm then refill.If you use a Mity-vac to bleed it draw 80 cc from each wheel or 10 pedal strokes if you do it the old way.Like Mihngram said 2 pints or 1 liter should be plenty,don't use old brake fluid, buy fresh fluid.Brake fluid is hygroscopic and an unsealed container in a damp shop will absorb moisture in a few months time.Good luck.

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