I'm going to go and bleed the entire system outstarting at the furthest and working my way back to the front. Hoping it works out.

 

I'd look at it from a stand point that something is acting like a check valve. Sounds like presure builds up in it and doesn't get to blead back for one reason or another. Could replace the proportioning valve also. I'm foggy on how those work though. Sure sounds like you almost have it though. You could also probably ditch the ABS. I'm shooting blind on this.. take some parts off a a non-abs model and slap em in.

 

Installed a new MC and went to bleed system...nothing at the rt front(source of the problem). One source told me to loosen the line and if it leaked it was pumping...loosened it and got nothing. Went back to old MC and all 4 were able to bleed and believe me I ran almost a half quart of brake fluid out and thru the system under brake pressure.
Test drive told me that the same problem is there after 10 to 12 city blocks. Brakes locked up on the rt front.
I am now under the impression and frustration that the problem lies in the ABS or proportioning valve... now when I was under the van today I did notice a bit of old(not fresh...a bit crusted) seapage on one of the braking system valves(two stacked together) located just below the MC on the frame rail.

Bewildered and At wits end. Fred

 

Is there some special alignment for the bolt that holds the brake line to the caliper housing. If there is ...that may be the problem and I'll pull it apart and take a look.

 

I doubt it's the problem but.. Should only go on one way unless you reall work to make it wonky.

 

If fluid pumped with the old but not the new MC, then the new MC is defective.

What state are you in?

 

Nebraska, Omaha

 

Dang, nobody is ever close enough for me to say, "bring it on over."

 

Alloro, I'll be right over. You can replace my ball joints and bushings.

 

Bring it on, I even have a 12 ton press sitting here. It should only cost you about $600 in gas to get here.