Small Engines (Lawn Mowers, etc.): Craftsman 22 model 917-379070 push mower, wheels and tires, drive assembly

Question
I replaced a broken belt on the front drive assembly, but the spring that engages the drive slides across the bottom of the belt. I think that this caused the old belt to break and worry that it will cause the new one to break, too.
Is it a design flaw? Also, How do I tighten the belt?
Thanks for any help

Answer
 Hello Paul:

 You can View a Breakdown of this Mower at this Addy http://www3.sears.com/ and Click on the Lawn Equipment Box. Then Enter the Model Numbers 917.379070 and Click Continue. The Verify the Equipment and Click Continue. Then Select View Diagram of the Wheels and Tires. If the Transmission Spring Arm is Bent the Spring will Rub Also. The Spring Keeps Tension on the Belt. This is the Only Belt Adjustment. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

 Good Luck

 Respectfully

 John