So after replacing my entire brake system on the new VW project and I cannot for the life of me get pedal pressure or fluid to the back cylinders. I tried all night with a vacuum bleeder and even resorted to a rubber hose and human power. Blech. No luck. Ive got fluid to the front 2 but no pedal pressure (probably because the entire rear circuit is dry). There are no leaks or other bleed valves that I can find. Should I try and pressure bleed it (hook up some cap to the master cylinder and hook a positive pressure source thru the system) This is pissing me off.....this shouldnt be this difficult!

 

I don't know VW's very well but with older GM cars the conbination valve could detect a leak front to back and it would switch off Front/back and would require the mechanic to reset it. Second the bleeding proceedure varys depending on design some master cylinders require bench bleading because when mounts their angle will not allow air to get out.

I would bet you do have a combination of issues. Not being able to build any pressure (even pumping) would be concidered a major system failure on a GM car. These systems are designed so that no one failure of a wear item would cause complete loss of brakes.

 

Air in the line compresses, fluid doesn't. That's why you're having a hard time with trying to push it through. Try cracking both rear bleeders open and let the fluid gravity feed out. If it doesn't want to go that way, then try pressure at the reservoir. And from what I remember from back in my V-Dub days, the brake system isn't all that sophisticated as far as having a resettable prop./combo valve.

 

Nothing complicated....the donor chassis is a 67 Beetle. Just a master cylinder, brakes lines and pistons. Im gonna try again tomo.

 

I took an air compressor and blew thru each section of line. cylinder to rear t was good....rear t to brake hoses was good. Brakes hoses to steel line.....wait a second.....both brake hoses looked good on the outside but are completely plugged on the inside. Guess Im off to Napa tomo.