So I ordered a Motorcraft idler pulley part #YS-250 (F65Z-8678-AAA on box). The first one I got did not fit and made contact with the motor. It is part# F65E-19A216-AA (on part) I contacted the vendor I got the part from thinking maybe I received something someone had returned or messed up or whatever... well, now the replacement I received is the same thing.

Well, after examining the two parts and the part number further, it appears the first part is defective or something. It is the one pictured on the right and it has a lip where the bearing is while the other one does not. The front now lists the COO as Canada while the other does not. I'll try and install this replacement and report back. Perhaps I got one from a bad batch?

 

The bearing slides all the way to the lip. Use a socket slighty smaller than the OD of the bearing to move it so you don't put any pressure on the race. bearing is a 6203 ball bearing - $6 at bearing house.