Iron particulates from the cylinder walls (or from iron or steel cylinder liners in aluminum block engines) would constitute a magnetic wear metal. Chrome plating, which is also
highly magnetic*, can be scuffed off piston rings. (I believe the scuffed chromium particulates would also fit the definition of a magnetic wear metal?
![[Wink]](images/icons/wink.gif)
) Chromium's not only more highly magnetic than iron, it's fundementally harder - which translates to more abrasive in randomly shaped particulates grinding against precision bearing surfaces. Definitely not a substance you'd want bobbing around in the oil if it's too small to be trapped by the filter. EMBRACE & CHERISH the neodymium magnet from an old hard drive head actuater! It's a loyal, re-usable, inexpensive friend for your engine.
*There's a reason professional broadcast video tape used chromium dioxide as its magnetic medium instead of ferric oxide - the inherently increased magnetic properties of chromium allowed higher frequency bandwidth which in video applications meant increased picture detail response before everything went to digital recording and retrieval.
[ May 30, 2005, 10:38 PM: Message edited by: Ray H ]