Ribs breaking on AC belt

I haven't had AC for about 8 months now. For some reason my AC belt broke just before this period but I never bothered to fix it because I wouldn't need it during winter(I'm wondering it has anything to do with the way it was put back together after a timing belt replacement) I recently went to replace it but noticed my tensioner pulley was seized so I replaced that and put a new belt on. All the pulleys are spinning fine and the problem is not the belt breaking in half-it's that 1 or two ribs break off then the belt comes off the pulleys.

Is this an alignment issue with the pulleys? If so, how can I realign them? Is there an accurate way to make sure all the pulleys are aligned other than just "eyeballing" it?

 

Alignment could be off or it could be locking up and eating away the belt.

 

You should be able to eyeball it and see if it's out of alignment. All the bolts back in AC bracket and tight? What brand of belt?

 

Talk to me about the ac idler pulley you replaced, whered you get it? It was such a simple repair I replaced the bearing in mine but took note that if it is not pressed in far enough that it could easily be off.

You can hold a straight edge on the pully, and see if they appear properly angled, or if they may be on crooked.

What brand belts?

 

I would count the ribs on the new tensioner to see if is the same aw the old.