I am in the process of bringing a Craftsman 917.254860 back into working shape. It is pretty rough. (Briggs and Stratton 18 HP - 42 inch) The good news is that I got the engine started yesterday and it seems to run fine. When I took off the Flywheel Housing cover, I was surprised to see that the edge of the flywheel with which the Magnetron "fingers" are aligned was extremely rusty as was the metal part of the Magnetron. Since the engine seems to run fine (got rust?!) and it makes good power, I am tempted to button things up and go on to the next section of the tractor. Any reason for me worry about or clean off the rust on these parts? TIA for your help.

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