But, if you bulid a motor the right way, you shouldn't have to worry about particles floatin' around The only place I would reccommend puttin' magnets would be the oil pan plug- The best way to filter out undesired particles would be to use an oil filter screen- they're cheap, only $10 for 10.These make it easy to identify the "wreckage", and you don't have to worry about an epoxied magnet floating around freely in your shit when they decide to let go.I've been building engines as long as I've been able to hold a wrench, never heard of epoxying magnet in a motor :0
With normal engine wear, you be surprised how much metal shavings you'll find in there. You really dont even need to epoxy the magnets on, if using rare earth magnets they have enough strength to hold. Anyways, its been done for along time. It works, and is cheap insurance and helps out alot. Put some in the tranny pan too and you'll find some stick to that too.