Need Help With Drive Belt PLEASE?!?

[tygr1]

Threw the serpentine belt off on the fwy last night...got the car home ok...picked up new Motorcraft belt today, installed it, fired it up...I watched while the belt climbed/jumped over one groove/notch rearward on the AC comp. pulley.

Loosened tensioner, re-aligned belt...it ran fine for 5 min...go for a drive...10 miles later, belt shreds.

This problem arose out of the blue!

Anyone???

 

[tomustang]

follow the belt all the way around it's cycle, without it moving =, check if there's anything blocking the course, ie: wiring, brackets.

 

[PG98GT]

Check the pulley just in front of where it's jumping, in the direction the belt rotates. See if that component isn't loose or if that pulley isn't warped or vibrating.