Rotating Tensioner to Replace Alternator

Well, my alternator died this morning, and after deciding I wouldn't spend $450 for the dealer to replace it, I tried removing the old one, but was stumped at how to loosen the serpentine belt. Everything I read on here and in the Chiltons manual says I should be able to rotate the belt tensioner to releive the tension by putting the square end of a socket into the tensioner (on the bottom end where the smaller pulley is), but using all my strength I couldn't get the thing to budge at all. I even tried loosening the bolt at the top of the tensioner that looks like it holds it on, but this didn't help either.

So here's my question: In greater detail, which way exactly do I rotate the tensioner, and does turning the socket as if bolting/unbolting something really work? Also, roughly how much force is required?

With the belt on there as tightly as it is, it doesn't seem reasonable to be able to rotate an arm easily to loosen it. If I do manage to get it off, is it much more difficult to put back on and tighten?

BTW, this is on a 1998 Malibu with the 3.1 V6

Many thanks to everyone here for all the help

you've got the right idea, however you are putting the socket in the wrong place, if you look at the pulley (the tensioner one) the socket goes in the bolt in the middle of the pulley it self. As if you were trying to remove the pulley. This will release the tension on the belt allowing you to remove it. And it really should not be a whole lot of force as it should easily release tension once you put the socket in the bolt it self.
Try it.

It Is Not Difficult To Remove The Serpentine Belt. The Belt Tensioner Arm Has A Square Hole In It Near The Pulley Wheel. This Is Where You Would Plug In A Tensioner Tool. You Can Borrow One From Autozone (deposit Required) If You Purchase A New Serpentine Belt There. (don't Try Loosening The Tensioner Spring Bolt As This May Cause The Spring To Come Off It's Retainers).

You Will Also Need To Unbolt The Left Side Motor Mount. Then Lift The Engine A Few Inches With A Jack (be Careful Not To Damage The Oil Pan). I Put A 4x6 Pice Of Wood Between The Jack And Bottom Of Engine To Put Even Pressure Across The Bottom Of The Engine. Just Lift The Engine Enough To Allow The Belt To Be Removed.

Anyway, You Might As Well Replace The Serpentine Belt If You Are Replacing The Alternator. Also, It Is A Good Idea To Clean The Grooves On The Pulleys When The Belt Is Off. I Use A Triangle Shaped Needle File To Do This. Just Lay The File In A Groove And Rotate The Pulley.

If you put a piece of pipe on the end of your ratchet (cheater bar) and rotate towards the inside of the vehicle, the tensioner will easily move and release the belt. BB has good advice....this is the time to change your belt if it's cracked and showing its age. If you only change the alternator there is no need to remove the engine mount. The mount only needs to come off for the belt change.

If you put a piece of pipe on the end of your ratchet (cheater bar) and rotate towards the inside of the vehicle, the tensioner will easily move and release the belt. BB has good advice....this is the time to change your belt if it's cracked and showing its age. If you only change the alternator there is no need to remove the engine mount. The mount only needs to come off for the belt change.

Thanks for all the replies. I went back to try a few more times, and using all the force I could I still had no luck getting the arm to budge. I'm thinking the ratchet I'm using might have something to do with it, it's pretty short, like 10-12", and I remember reading that a longer one (24"?) was best. Maybe the arm is just stuck, although when running i see it move back and forth. I'm just hoping now I didn't damage the tensioner with all the stuff I've done to it.

Anyways, with the alternator, my parents were getting afraid of me breaking something, so they offered to pay for a shop to do it. Disappointing for me cause I love to tinker around with the engine, and the alternator seemed like such an easy thing to replace, if not for the damn belt :confused: