Are the rear brakes adjusted properly?
Oftentimes slack rear shoes will cause the brake pedal to sink before
catching.   Adjust rear brakes after loosening parking brake cables,
then retighten parking brake cables. If the rear brakes are not self
adjusting then the horizontal tension spring may be installed upside
down or the adjuster mechanizm needs cleaning and lining.

2009/10/23, William Greenamyer <greenamyer@yahoo.com>:
> Well, replaced the master cylinder.  Seemed to be fine but as I used the
> brakes, the pedal worked worked down to the floor.  The pedal has pressure
> but if you push hard enough (like a panic stop), the pedal goes to a metal
> stop which I guess is the top of the brake lever hitting something in the
> brake drum or some bracket.  Does anyone have any ideas?  There are no noted
> leaks anywhere at present so far as either I or my mechanic can find.  That
> indicated the master cylinder.  No I would suspect that power booster.
>
> William
>

--
Chris S.
Disclaimer: "Death and serious injury may occur"