1.8 belt tensioner

Hi wanted to change my drive belt and couldnt slacken the belt of all i could see was the 13mm bolt from under the idler pully thats loose and the pullys still solid the only other thing i could think of was the ring of 8mm bolts around the pully but didnt have owt at home to get to them so if thats the case ill bring some more tools home thanks.

Not got my freelander handy to look but usually all you have to do to change a belt is put your spanner or socket on the central pulley bolt and use that to release the tensioner enough to be able to lift the belt off - two minute job (usually...)

had a quick look at the end of the pully and didnt notice a nut but it is all covered in mud so ill get cleaned off and have another look thanks