Im trying to replace my alternator, however I have run into an issue on pretty much the very first step. I put the 3/8" drive into the slot to release the tension of the tensioner pulley to get the belt off. But when I tried to turn it, it made a cracking sound. When I looked at it the top piece of the slot that the drive goes into broke off. Now the opening is too big for the drive to turn it. Is there another way to release the tension on the belt?

 

Draw a diagram of the belt, and cut it , make sure you have all the parts before doing so

 

That gets the old belt off but hows he supposed to get the tensioner released to get the new one on?