LT1045 throws deck belt

[comtech]

I had same problem. I fixed it by removing one pulley, moved the bolt spring holder for the front pulley to the back of deck for the tension spring for the new configuration. If you look at a diagram of the mower decks for this model, one of them shows a single pulley configuration. I purchased a belt based on that part number, put it back together and it worked fine. I did have to drill the bolt spring holder hole larger because bolt didn't fit, but it drilled easy. hope this helps.