Rude Flywheel, dont wanna loose the polarity

[rentprop1]

picked up an old flywheel today , has some rust on the underside, need to clean it up, I think the best way would be a wire wheel on the air grinder.....

what do I have to be careful of not to screw up the magnetism ( sp )

I am replacing a gremlin flywheel that I think has lost the correct polarity, a shade tree mechanic put the wrong bolts on the top of the flywheel when attempting to remove it, messed up the threads and drilled and taped for the next larger size bolts....I think the drilling might have messed up the polarity ??? what says you all ???...thanks

 

[emdsapmgr]

Re: Rude Flywheel, dont wanna loose the polarity

An unlikely scenario. However, magnets can be affected by shock-such as dropping the flywheel from ten feet, or repeated knocks. You have both the big magnets on the outside and the timer ring in the center-both can cause issues. If you are going to use the rusty flywheel, make sure you "lap" the crank to the flywheel taper area to be sure it is clean prior to installing the key and torquing.

 

[F_R]

Re: Rude Flywheel, dont wanna loose the polarity

It takes a very strong magnetic field to change it, much stronger than anything you can do to it by drilling or wire brushing. In fact, I am not sure it is even possible with modern magnets. Your shade tree mechanic certainly didn't mess it up by drilling.

Old iron magnets could be damaged pretty easy, but they haven't been used in outboard flywheels since WWII.