I'm looking all over the place on here for info about installing the 19 mm master cylinder. I rebuilt my pedal cluster and I put the new master cylinder in, then filled the reservoir with fluid. Pumping the brakes isn't putting the fluid into the lines when I open the bleeder on the rear passenger caliper. This is a brand new master cylinder. Do I have to fill it or prime it before it pumps properly? Thanks

Make sure the plunger rod which attached to the brake pedal and goes inside the MC has 1mm clearance when released. If your plunger is keeping the MC from releasing fully, you won't get fluid.

Thanks! I'll go check it right now.

Do a search for brake bleeding.

A friend came over with a pressure bleeder. WOW! Talk about easier than pumping the brake pedal. I'm going to get one of those. The right tools make the job go so much more smoothly.

Recommends you all wear safety glasses, brake fluid burns like fire in the eyes, no shit, it hurts like hell.

Yeah I'll vouch for that one...

Was bleeding the slave cyl on my 944 one time, was over visiting my parents. From time to time my dad will wrench on cars with me to pass the time. I remember telling him "Now slowly push the clutch" he stomps, the line pops off the nipple, fluid SHOOTS in my eye.

I'm going "AHHHHHHHHHHHHHHHHHHHHHH MOTHER****ER OH MY *** HOLY **** IT BURNS WHAT THE **** AHHHHHH" as he's going "what happened? you okay?" with my face covered in the stuff Funny now of course. At the time, I think it was on a scale of 1 to 10 an easy 7.5 to 8 for pain.

Anyway..... yeah. Wear some safety glasses.

I would suspect a clogged rear brake flex line.

Usually you have to bench bleed a brand new master cylinder before installation.