Ok so I'm going to change my alternator and was trying to figure out how to take the tension off the belt. First I was going to buy that tool but then found a thread about the tension pin on the tensioner. So as suggested in the thread I start to pull on the belt just below the alternator so that I could push the pin into place. At first I couldn't seem to do it myself so I asked my buddy to come give me a hand. Between when I pulled and he came over to help there was no tension on the belt and the tension pin isn't in place holding it up. Any suggestions? Its seems like if I broke the tensioner I would have heard something snap or break. I'm hoping it's nothing too major fingers crossed. Help please.

 

I just replaced one of mine. similar problem. Took off while doing studs and felt kinda of. Putting it back on it was still and almost no tension. Explained the odd wear on the backside of the belt. Best to replace it.

 

There ae 2 basic reasns for no tension, the spring is broken or the tensioner froze in place unable to adjust to wear/stretch of the belt.
Replace the tensioner and probably the belt as well.