Help - rear brakes dismantled, can't compress the piston??

[ttaw2]

as the title says, i've got the old pads out, but can't shift the piston to make room for the new thick pads...

Any ideas, the car's up on stands at the moment

[Del_GTi]

I could be wrong but i think they may be like the golf, if so, the piston screws in.

[ttaw2]

Got the piston moving and like you said, it's threaded.. Don't quite see how unscrewing it will help me to get the pads in as that onl makes the gap smaller...

Am I being really dumb and missing some mechanism that locks the piston in place...?

I've disconneted the handbrake btw!

[ali]

Try turning it the opposite way, so as to open the gap (there is a special tool for doing this, Halfords sell em £20). Undo the brake fluid cap as you will be compressing the pistons. Make sure none spills on anything