Do I need to bench bleed my new master cylinder if all the brake lines are dry? I haven't found any evidence to confirm this, but my guess is that the point of bench bleeding is to save the PITA of pushing all the old fluid out of the lines just to get the air in the MC out. Figure since I need to do that anyway, starting with a bled MC won't really save me much time, and just adds an extra step.

 

yes if not you will be bleeding the whole system a bunch of times. Make shure when you bench bleed do not bottom out master may cause the seal to get cut.

 

yes i would bench bleed it and then gravity bleed the system once the master is in place. Once it is completely gravity blead i would then pressure bleed the system to ensure no air is in the system and you don;t have any brake fade.