serpentine belt change

Just changed my serpentine belt on my 2000 Pontiac Montana with a Gator Back v-groove belt from Goodyear, its been about 2 weeks now and i just peeked under hood to check oil and I noticed that belt is a liittle bit chewed up on the outside???? I checked all pulleys that belt rides around on the outside and they all seem smooth and free spinning, what could be causing belt to get chewed up on the outside??

It only happens when the belt is on one of the pulleys wrong-- it is shifted one groove to the outside on one pulley- most likely the one you cannot see the best-- probably the drive pulley-

It only happens when the belt is on one of the pulleys wrong-- it is shifted one groove to the outside on one pulley- most likely the one you cannot see the best-- probably the drive pulley-

Maybe i didn't describe problem correctly, I should of made it clearer I'm sorry, the belt is not getting chewed up on the outside edges the actual back flat side of belt is getting all chewed up. Not the grooved side of the belt the flat side of the belt is getting chewed.
Thanks for any help

The only time I've had belt problems is when my harmonic balancer was going out. The belt ended up riding half on/half off of it before I had a clue what the problem was.

You should follow the belt around its full path visually. I have in the past put mine on and accidentally got it rubbing on something it should not be rubbing on. I had to release the tension, reroute it and then reapply the tension. Luckily I saw it before I started it, so I don't know if it would make a noise if left that way.

You need a water pump :eek7:

Pull the belt off the tensioner so you can spin the water pump pulley by hand. I'm betting it won't want to spin very well.

If you remove the plastic guard over the water pump pully its easier to see.

That's the most likely item to chafe on the back side of the belt.

I just changed my tensioner and serpentine belt a week ago on my 99' Montana 3.4L. Since I rarely do repairs myself, I was a bit nervous that I had done it correctly, but with the economy the way it is, I'm looking to save wherever I can. I have the exact same belt mentioned above (Good Year Gator V-groove) $32 and the tensioner was $41. Make sure to save your old bolt, as the new tensioner did not come with one!! It's one 15mm bolt. So I figure I probably saved at least a couple hundred bucks doing it myself. In my situation, the van has 107K miles and the belt was still in tact, it was the tensioner that blew up, the plastic wheel had disintegrated due to heat and wear ( I guess ). After doing some research online, I found out that both the belt and tensioner should be replaced about ever 60-70K. And that you should always replace them together.

My question is about the tension. I don't know how to "adjust" the tension. Is it self adjusting? Or is there something else I should have done? Basically, I pulled the tensioner forward until I could get the belt on, then gently pulled it foward to adjust the belt and make sure it was aligned properly around all the wheels and pulleys. It seems to be working Ok, is there any thing else I should be doing tension wise? Thanks for any help.

You did just fine......the belt tensioner provides the recommended tension to the belt automatically......

You did just fine......the belt tensioner provides the recommended tension to the belt automatically......

Thanks for the reassurance!! :)