so been working on my car and found that the alternator belt was lose and i tighten it and then couple days later the belt need to be replaced then drove it around for awhile and then the new belt i put on was lose again. so i tighten it and now the tension bar on the alternator was all the way up. now the dame belt is lose again and cant adjust anymore. i took the alternator to the part store where they tested the battery which is new. and the then alternator. found out that it has gone bad no big deal replace it right. But what about the belt? why is it keep getting lose any ideas? could it be that the engine bay is too hot making the belt expand to the point that they need to be replaced?

 

LOL, that sounds like two different mysteries. Fortunately one was resolved. Honestly that sounds weird... I can't say for sure what's going on so i won't, unless i saw what was up. Pointing out the obvious, regardless of the belt loosening on it's own a new one shouldn't wear out. Make sure your pulleys aren't causing this. If they sit for a while rust likes to form inside where the belt rests. It doesn't sound like the bolt and nut on the alt level piece attached to the water pump cover is slipping but keep an eye on that. Also make sure you have the right size belt. I'm sure your local auto parts store can handle that.

 

Also, don't be afraid to double check the obvious. Sometimes our biggest problems come from the simplest mistakes. May want to check the torque of the nut that holds the pully assembly down. Make sure it's tight. Watch the pully closely and make sure it's not vibrating or jumping around at all. It needs to be perfectly balanced.