Yes, they do slip. No, you can't keep using it. Unless you have an outer pulley bolted onto the front it will fly off. I have lost two on my 292. I lost one, when I started it up and it just dropped on the ground. I lost another while I was driving along at about 65.
I have a half dozen from other vehicles laying around that have slipped. Sometimes they come in handy such as on the press.
