Sorry for bringing up this old topic one again, but while I appreciate the idea of priming as a means to remove air from the master cylinder before installation, I cannot see how all the prime is maintained as the cylinder is put in place. Some air must be present after installation I think.
Initially, on the bench, you can contrive to achieve a full prime and then install blank plugs to hold the fluid inside the cylinder. However during installation some fluid would leak out of the output port during the connection process, thus allowing air to enter at the top of the vertically oriented cylinder, so defeating some of the priming. The fluid left will be that up to the level of the outlet port - maybe that’s enough to do some good?
Perhaps all that is needed on the bench is to set the cylinder vertically, backfill through the outlet port until fluid appears at the inlet port and then remove the outlet fitting when fluid will seep out for a while. Then do the install.
Agreed there will be less air than if no priming were done but it is by no means a slam dunk (and I doubt Jaguar did this in production - far too complicated and potentially messy I would say.
Nevertheless I am going to try it during my upcoming fitting of a new master cylinder.
My situation is that the first pedal application is long and the subsequent ones are short. I have done multiple bleeds using three different techniques, and I am absolutely convinced there is no air in my system so I suspect that the inlet valve in the master cylinder is not closing as promptly as it should when the pedal is first depressed.
We shall see.