Fan belt jumped of pulleys
2000 e-150 4.2 v6,61k on it. I got the belt off and looked at the pulleys. I found that the automatic belt tensioner pulley seemed froze and also tried to do counter clock wise and bring it back off tension and it wouldn’t move either. A littel w-d and got it working. my question is should I replace the whole mechanism or can I just replace the pulley by itself? also I guess I should replace the idler pulley since I’m in there. Thanks.