I have a 4600 with 72" Quadcycle Deck. I acquired this recently and the mower deck belt is too loose. I see that there is a tensioner spring attached to an arm on the tensioner pulley. However, when the tensioner is moved to a location so that the belt is adequately tight, the far end of the spring is almost to the point where the chain is anchored on the deck. It appears that the belt may be too long. The spring was not attached to the spring chain when I got it. How should it be attached to the chain? I have downloaded an owner's manual but it doesn't help much. Any ideas or guidance? Thanks.