Power steering pulley

Hi all.
My power steering pump pulley appears to be sticking out too far and is chewing the outside few ridges off my auxiliary belt. I've tried turning the pulley round but it's not fixed it. It appears to be about 5mm proud.
Any ideas on what could be wrong?

Thanks in advance.

Roy

Do you have a picture of the problem pulley

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Hopefully you can see these images.

Has anyone got any pearls of wisdom about this? Why the pulley would be sticking out 5 to 10mm?
Cheers.