Thank you for your question.
I am sorry you are having a problem with the tractor. I will be able to assist you with installing the belt. I recommend checking the condition of the belt first. If the belt is worn, it should be replaced. The part can be ordered from our parts website:
Sears Parts Direct
I recommend removing the mower deck to install the drive belt. With it off you have more room to work and better access to the drive belt. The first image has the instructions for removing the deck. The second image has the instructions for replacing the drive belt.
If you need further assistance, please reply below with more details.
If you do not feel confident repairing this problem yourself, then you can have it repaired at your home by a Sears technician. Here is a link for the website:
Sears Home Services
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