Cleaning of 912 Stator flywheel

You could take a Dremel tool with a buffing pad and some polishing compound and clean it up. 

hello Luis

Given you have it off take the flywheel plate apart from the actual magnet plate.  There will be 10 screws, on some older versions there are only 5.  The newest ones have 10 with the bolts of a stainless material I believe.  The black plate can be painted again but be sure to cover the taper on the inside and not to paint the taper.  

For the magnet ring normally just some Scotch brite abrasive pads will clean off the rust.  Wash it down with some paint thinner after or carb cleaning spray.  Now take that part and give it a light coat of clear lacquer paint.  (not too thick on the inside) This prevents the rust from coming back for a very long time, it is basically what it has on it from the factory.  Assemble the plate to the magnets, there is no specific order, the magnets alternate.  The screws are all the same length so some stick past the plate face and some are flush, that is normal.

Cheers

I forgot about Scotchbrite. Guess I'm getting old.😀