Not sure what the previous poster is carrying on about, if the belt were off-center when you levered up the tensioner, it would self-center when you cranked the engine.

More than likely you have a worn tensioner pivot or tensioner pulley which is allowing the belt to scuff as it rolls across the pulley since it's out of alignment.

Remove tension and check for any play in both the tensioner pivot and the pulley. It wouldn't be unheard of for the tensioner pivot to have had it after chattering like it was with the bad shock.

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Current stable:
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