Thank you for your question.
I am sorry you are having a problem with the mower. I have looked up the model number you have submitted. There is not a belt adjustment on this mower. There is a spring on the transmission that keeps the belt tight. To check the spring you will need to remove the belt cover on the front of the mower. Then look for the spring that connects to the transmission and the mower housing. If the spring is connected, leave the cover off and start the mower. Then engage the drive once it starts slipping look at the pulley on the transmission. If it is not turning, the belt is slipping. If the belt is old, I recommend replacing it first. While installing the belt you can scuff up the v part of the pulley with sand paper. You will also want to clean any oil that is on the pulleys. Oil will cause the new belt to slip.
I hope this is helpful.
Please let me know if you need further assistance on the repair of the mower.
Here is a link to order any parts you need.
Sears Parts Direct
If you do not feel confident repairing this problem yourself, then you can have it repaired by a Sears technician. Here is a link that will provide the nearest drop-off locations:
Sears Home Services
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