Is this anything to worry about? (bearing shells)

[The Black Flash]

The back of my crankshaft bearing shells appear to have been rubbing, leaving marks on both the bearing shell and the cap:



All four bearings have similar marks. Could the shell have been fretting in its seat ?

I've no particular reason to suspect anything was wrong, I just wondered if this was normal or a warning sign. The big end shells didn't have these marks, which is why they stood out to me.

[stevieturbo]

wouldnt say anything looks particularly odd there

[GavinPearson]

I don't think there's an issue. As the bearing conforms to the cap & block bore it won't seat perfectly so you do get some localised staining, and it looks much like what you have.

Clean the marks off with wire wool but nothing more abrasive than that.

[The Black Flash]

Good news, just wanted to check, thanks

[Boosted LS1]

The back of the bearings been coated by the look of it and heat has caused the coating to come away. It doesn't look like fretting to me so I wouldn't be concerned either.