How to slacken the alternator Belt Tensioner

[mgbond]

The AA guy did this the other week but I neglected to see what he did.

I think my belt need to move over one on the alternator.

The tensioner has a torx fitting in the middle and I though you just go into this and turn so it moves the tensioner.

Any ideas?

[anotherdom]

1/2" square drive into the tensioner arm - it moves fairly easily.

[mgbond]

Ah, got it. Know exactly what you mean.

Cheers