I own a 48" Exmark Lazer CT. I bought it used with 150 hours for home use (2 acres). I am not very mechanical so this is probably a simple question. I threw the deck belt yesterday. The engine was cold and sputtering when I engaged the PTO and it stalled and threw the belt. I lifted the top of the deck, saw the diagram showing how the belt should feed through the pulleys, pulled on the belt to get some slack and placed it back on the pulleys. My question is how much tension should be on the belt? It seemed too easy to merely pull on the belt with one hand and feed it around the pulleys with the other. There is tension on the belt, I am just not sure if it is enough tension. Maybe this is normal. I have never worked on a zero-turn mower before and that is why I ask this question. For additional information, after I fixed the belt I reached under the deck and rotated one of the blades by hand. The other blades rotated as well but only sporatically...they didnt follow the rotation of the blade I was turning exactly. In other words, the belt was loose enough such that it slipped somewhat when I rotated a blade by hand. I checked my owners manual and all it says about the deck belt tension is "self-tensioning, no adjustment necessary". I mowed after fixing the belt and it seemed to mow ok, but I couldnt tell if the belt was slipping on the pulleys or not. Thanks for the help!