Need a little help 2000 gmc savana

[Oilkann]

The belt keeps walking off the crank pulley just a bit. Can figure out what’s causing it .Replaced the tensioner and idler pulleyReplaced the tensioner and idler pulley

[txab]

Did this just suddenly start doing this or did you changed any other belt driven devices recently? were you having the issue prior to tensioner and idler change? Harmonic balancer/pulley running true and not wobbling? Check alignment across the face of pulleys.

[Oilkann]

I purchased the vehicle , and noticed it was shredding the belt like that so I changed the tensioner and the idler pulley trying to clear it up.  Bit both didn’t help a thing 

[txab]

Then check face of pulley alignment with a straight edge.

[Oilkann]

I’m curios as to what you can do if it is a bad pulley alignment , being all the items just bolt in place no shims , also I’m pretty sure I stripped my crankshaft bolt out check to see to see if it was tight