So I installed a new battery and a new alternator earlier this week. Awesome.

But today I was on my way to work and lo and behold my car dies.

So here's what happened leading up to that point. Yesterday all of th electronics in my car started acting up and my tach started going haywire. Ok, that's fine I don't need my tach. Well today my radio starts messing up and my car starts sputtering and the transmission light comes on. A quarter mile later, my car is dead. I'm thinking when I installed the alternator I did not tension the belt correctly and it has not been charging the brand new battery this whole time and the reason my car died while running today was because I had my radio and lights on and there was too much power being drawn an used for only the alternator to run the car.

My theory supports the alternator is fine except that it's not charging the battery because I got a jump, and the car powered up just fine. I unhooked the battery while it was on and it kept running.

So my real question is, is this most likely a problem with how installed the alternator and if so, how can I figure out I need to calibrate the tension on the belt? Whats the measurement or amount of tension I need to put on it and how can I figure it out?

Thanks fellers!