just finishing dismantling my engine and when i was putting the pistons and connecting rod away i have noticed putting back the caps that there was a magnet effect between the two parts ¨(caps and connecting rod) is this common and how can i demagnetize these parts.
Mike,
That's a new one on me. I'm surprised no other responses yet, but expect your post not showing has kept some from reading (which is why I cut/pasted to post in quote). Have you tested the rods and then the caps separately to see which has the "attraction"? I suspect you could use any bolt or washer handy to cross-check.
I do know it's possible to add magnetism to any ferrous metal but in an engine, I'm not sure why. The exception I'm aware of is using a magnetic drain plug to capture metallic bits so that removing them are easier.