I didn’t have my pedal going to the floor, it was just a lot softer with the car running.
I made up a short brake pipe with a syringe on the end of it and removed one of front brake pipes off the master, fitted the syringe brake pipe and pumped fluid through.
A little messy so watch your paintwork with rags, but I did manage to get quite a few bubbles out of the system that way.
Doug
