Bleeding the Brake Proportioning Valve, Please post your "Secrets" here Options

[Brian Mifsud]

I have unsuccessfully attempted repeatly to bleed my brake system and get a firm pedal. I've rebuilt all four calipers, and installed a rebuilt 19mm master. The rubber lines have been replaced with Stainless Flex lines.

I've run literally quarts of brake fluid throught the system using an "Eazy Bleed" at each caliper and still the "soft pedal" persists (can't lock up if life depended on it)

I have not yet replaced the hardlines that run through the body and I know those things can neck down with corrosion over time causing a big pressure drop.

Last on the list of suspects is the proportioning valve.

Are there special "Tricks" that work in getting all the air out of this thing?

I've yet to take it out of the car and take it apart.