Thank you for your question.
I am sorry you are having a problem with the tractor. If the belt smokes and breaks right away, I suspect the belt is on the wrong side of one of the belt guides or brakes. Before running the mower again, I recommend removing the belt. Then spin the idler pulleys on the deck. They should turn freely. If they are ok, move the engagement lever up to engage the blades. Now turn the mandrel pulleys. They should turn freely. If the pulleys are fine, go ahead and reinstall the belt. Just be sure the belt is in all of the pulleys. Each mandrel has a brake, which has to be moved out of the way to install the belt. I posted the instructions for installing the belt. Click on the image to enlarge it. In the image, I marked the brakes. On the left side you need to remove the guard to access the brake. Once you have the belt on, run your hand along the belt to be sure, it is not over a belt guide.
I hope this is helpful. Please let me know if you need further assistance.
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