Originally Posted by symmetricon

You can put it on the right way or the wrong way. What your pics showed us is the result of the wrong way. I have seen them put on backwards from several local people, it easy to do.

Think about it this way. If you mount the bearing only to the puly tensioner, then slide the pully over the bearing, the pully can come off the same way. The ridge that captures the bearing must face or go on facing the post on which it mounts. Makes sense?