Bleeding brakes

[Captainfab]

It sounds like the proportiong valve is doing it's job. Likely what happened, is when you started the bleeding process, you had, no brake fluid at all in the front system, or the rear system. The proportioning valve saw this as a leak, and the valve slid over to block off the system that was 'leaking'. Is the front reservior on your master for the front or rear brakes? Which proportioning valve are you using? Basically what you need to do, is get the valve in the prop valve centered again, and get some fluid in that system by gravity bleeding first. Then go about your procedure of pressure or vacuum bleeding.