Hi.
I was having problems with not having rear brakes and weak fronts so i replaced my master cylinder all calipers and put a portioning valve in the line that goes to the rear as the tech article said. and took the stock one out. i have the potion valve open all the way and i still have no rear brakes. would any one be able to guess why I'm not getting any pressure back there. I have bleed them 3 times now and still noting its the same way it was before all the work. I blew through all the lines with cleaner and compressed air to make sure there was no restrictions and replaced all rubber lines.
I'm stumped!

 

vacuum?

 

the front ones are better when the vacuum is up but the rears still have nothing.

 

which prop valve do you have installed? And do you have a picture of how it was installed?

 

My valve is installed exactly as this one. I have a jeg's valve I set it for the least and I blew threw it to make sure there were no restrictions before i installed it. it sees that the rear calipers want to clamp but they just don't then i let off the pedal the plungers go back into the calipers. I'm confused

 

rear calipers siezed? maybe a bad booster. if you didnt bench bleed the master, you probably still have a lot of air in there too.