Master Cylinder Question
 

I just replaced the proportioning valve on my 71 Duster and when I had all the lines disconnected, the rear bowl of the master started to drain, but not the front. Is it normal for the front to stay full when the lines are off? What keeps the fluid in, but not on the back? Thanks.

mine leak if i take them off, was the front fuller than the rear? or maybe the front bail seal as a tigher fit

Front and rear were both full. The rear actually emptied out and the front just stayed full.

OK now I'm trying to bleed the brakes and I can't get fluid out of the rear wheel cylinders. When I hook up my pressure bleeder, I can get fluid out of the front bowl port, at the prop valve, but not out of the outlet of the prop valve. Any ideas? It's a brand new prop valve from Inline Tube.