Braking Problem

[richystran 7 3 Cars]

I just replaced a front caliper on my 205 1.6 as the piston was completely corroded and i had a spare caliper lying around. Ever since this i have the brakes locking on the rear of the car, which makes for very scary driving, i have blead the car all around to see if this cured it but to no effect! The car is also running a 309 gti rear axle, so it disc all around.Anyone an idea what would be causing this?

Thanks

[welshpug 1,655]

compensator valve stuck open.

[richystran 7 3 Cars]

And how would I fix the welsh? Is there anything I can do or is a new valve needed? Thanks!