Not quite as damaging to radiators and such, but just as lethal if you're in the way......I've had the little bent-over generator and alternator fan fins separate, usually when you're using a stock-diameter pulley on an engine capable of 6,000 and more RPMs. That's why Chevy and I'm sure others used to install larger diameter pulleys on high-red line engines from the factory. I've managed to implant some small, "outie" dents on a '34 Ford hood (Chevy engine) and a '55 Chevy hood in the past. The noise is almost like a gun shot. DD