Where can I find a diagram of how to install a belt tension pulley on my Kenmore dryer Series 70 ?

For that type of info you have to buy a SERVICE MANUAL.

Try any of the following Sears links :

Sears on-line website

http://www.sears.com/Service

http://www.searspartsdirect.com/partsdirecta

http://www.searspartsdirect.com/partsdirectb

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