Thank you for your question.
I can understand you wondering how to adjust for the slack in the drive chain.
I am sorry to tell you that there is no adjustment and that you will have to replace the drive chains to repair the slipping problem.
If it were me I would use a chain break to remove one link and put a half in with a master link.
If you are comfortable with repairing the chains your self I can direct you to some tools that would help you.
The chains however, are not very expensive.
They are in the range of about $10.00 each so I would replace them rather than repair the chains.
The part number for the chains are: Primary chain is part number: 532430645 for about $10.00 and the secondary chains part number is:428069 for about $10.50.
You can order these from:
Sears Parts Direct
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
I hope this will help.
Thank you for using Manage My Life.