help with porportioning valve

[sasexplorer]

my friend has a 97 psd he put new brakes on the front including everything. we bled them and he went down break neck to check them[its a real road] and had no brake fluid by the bottom. checked for leaks and tried to rebleed them nothing helped. the back breaks lock up. the brake pedal wasnt touched when we put the calipers on. so that elinates the master cylinder.the pedal goes from hard to soft when ever it wants. im thinking its the porportioning valve. i didnt see any abs pup so that elinates that.any help will be apreciated.

[Aces'n'8s]

Originally Posted by sasexplorer

my friend has a 97 psd he put new brakes on the front including everything. we bled them and he went down break neck to check them[its a real road] and had no brake fluid by the bottom. checked for leaks and tried to rebleed them nothing helped. the back breaks lock up. the brake pedal wasnt touched when we put the calipers on. so that elinates the master cylinder.the pedal goes from hard to soft when ever it wants. im thinking its the porportioning valve. i didnt see any abs pup so that elinates that.any help will be apreciated.

Did you check every connection in the brake system for leaks? Sounds to me like you have an opening in the lines and fluid is leaking out, and/or air is getting in.