A buddy of mine had put in a new cam. Well he asks me to come over and help adjust the lash in the rockers. We go over it, every cylinder. I'm pretty condident I have all of the rockers tightened down and the lifters loaded up. So I tell him to crawl out from under the car (where he had been turning the crank over) and start it up. Well he cranks it and *BANG*. Sounded like a rod slaping the pan or something. I'm pretty sure he shat himself and then killed the engine. I walked towards the engine thinking "how the hell did we break something in the engine??". Well, I go to turn the motor over slowly by hand, and I reach for the breaker bar to put on the crank. Guess where it was.. Still setting in the crank pulley. I ask my buddy, "what did you use to turn the engine over?", "the breaker, why?", "what did you do w/ it when you were done?", "uh... well... I really don't know..OH ****!". I proceded to laugh at him for the next hour.