Replaced belt, new belt is burning when pump engages

I have an Amada ALW480DAW. The belt burned/broke when I accidentally overloaded it. I replaced the belt, and now it agitates perfectly. However, when the pump engages to drain the basin and the idle pulley thingy relaxes the tension on the belt then I can see/smell that the new belt is burning as the pulley spins and the belt stays stationary.

Any brilliant ideas? Is it possible that there's just some residue from old belt that needs to burn off? Or perhaps the pulley is shot? I did notice that the pulley was a bit rough inside, but I'm not sure if that's a big deal or if that's normal. Perhaps when the old belt burned it damaged the pulley, which is now damaging the new belt.

Thanks in advance!