I need help I got a 2013 z6ex I replaced the master cylinder and been messing with this thing for the last few days and can't get brakes to build pressure front brakes push out fluid but won't build pressure and back brakes just keep gurgling not pushing fluid out anyone ever have this problem

[2015 Z Force 800 53/Trail EPS]

Probably going to have to back-bleed or use a power bleeder on them. Sometimes it's impossible to do it the normal way.