If a soft pedal can be pumped up and becomes hard, that points to seals in the master cylinder or some anamoly with the calipar (warped rotors have similar symptoms). Air in the lines will have the pedal soft until enough pedal travel has occurred to compress all of the air and then it goes hard, often progressively. This should be repeatable any number of times with the same amount of soft travel before going hard. If it is air in the lines, you could pump a hundred times and you'll still have the same amount of travel before the pedal goes hard.
RV-6A / IO-320, Flying as of 8/2015
RV-10 in progress
Last edited by lr172 : 08-21-2018 at 10:14 PM.