How do you bleed the isolation/dump valve

you need to have the brake system preesure bled

You bleed the RWAL by loosening the line fittings. It may be tough to bleed it, air gets trapped in those things badly. You are better off not allowing air into the RWAL or the master cylinder in the first place. Pinch off the rubber lines to keep fluid from draining out when you are doing wheel cylinders or caliper replacement. Always keep the brake fluid reservoir full when working on the brakes because you don't want to get air into the system, especially with any kind of ABS.