I don't know if it's lens compression or an optical illusion, but it does look like it's crooked. It looks like it's pointing over at the pillow block/arm. ETA: Almost like the arm the idler pulley is on has a little bit of twist in it. I would think if you could get that clevis further out on the arm towards the pulley it might take some of that twist out (assuming it's not an optical illusion) .Idler probably needs to be a sprocket to help prevent it from jumping off. Is current idler sitting crooked?