Got a Novi 2000 on foxbody ran fine 18psi was doing other maintenance and noticed blower pulley was loose. Bolt tight but pulley loose? Pulled out bolt and pulled off pulley and both keys are warn down till they were almost round and the front of the pulley was warn by what looks to be where it was rocking back and forth on. How did this happen? I guess I need a new pulley and keys but what caused it?

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