Thinking about buying a 42" MTD 16 hp for 275obo, lady states "it was running, but my husband said it needs a plastic piece replaced on the flywheel, he gets home after dark and has no light to see to fix it". Spoke with a lawnmower shop who said if I bring the flywheel they'd fix for 50. I've never removed a flywheel or don't remember, I believe you lift off the screen, and maybe one bolt is on top, but the guy at shop says you have to drill out rivets, tell me if I'm close, and never having seen the internal guts how to recognize when I get in there. Thanks loads, rick

Actually would help to know what brand engine, and if its electric or pull start (or both)...
But you have to take the shroud off... that screen is a finger guard, should come off via screws not rivets.. only plastic piece I can think of would be the fan on newer model engines.. the flywheel should be steel or aluminum... flywheel key aluminum.

Unless the guy was maybe talking about the starter gear, flywheel ring gear on some are also plastic... or if it has pull start.. the starter pawls...

Basically remove the shroud.. finger guard screen.. then the nut that holds the flywheel on... (I'd use a puller for the flywheel, safer) and pull it off.