Brake regulator

Please help, got a 93 sportline that has failed it's mot due to rear brakes sticking, my mechanic has double checked everything and has also changed the master cylinder, still the brakes stick after a couple of miles. He got round it by taking off the brake regulators at the master cylinder and now they don't stick, cannot find replacement regulators anywhere, anyone got any ideas about sourcing some or do you actually need any fitted?? Thanks guys any thoughts would be appreciated 

Hi,
Are you talking about the cylinders that screw directly into the bottom of the master cylinder?
If so, then they set the max amount of pressure that the rear brakes will see, this is to stop you from locking the rears up before the fronts and sending you into a spin.

If the cylinders are connected by brake pipe from the master cylinder then those are used to hold some residual pressure against the drums. You will find a pressure relief valve under the rear axle that deals with stopping the rear brakes locking up before the fronts.

Cheers Ade

Yes the only brake regulators on the car are screwed into the master cylinder, there are non at the rear. If I disconnect them from the master cylinder the brakes work fine but when I refit them back in and brake hard which is needed for the MOT test the rear brake shoes continually rub. The only way I could get the car through the MOT was to leave the regulators out of the master cylinder. I know they are to prevent rear lock up, but I can not source another pair of regulators. As I cannot get the parts I do not know what to do, would changing the rear brake cylinders fro 17mm to 14mm help? Any suggestions would be greatly received. Desperate to get the car back on the road

Cheers Ade
Yes the only regulators on the car screw into the master cylinder, there are none at the rear. The only way I could get the car through the MOT, for the brake test, was to take the regulators off, when I left them on it failed because the rear brakes stayed rubbing.
I know the regulators prevent rear lock up but I can not source another pair anywhere. Would it help if I changed the rear brake cylinders to 14mm rather than 17mm , as I've seen suggested on here previously?

As the regulators are not available to buy I am at a loss as what to do, can I just drive without them, I only do 1000 miles a year and don't drive it fast. Any suggestions would be greatly recieved