Main bearing wiper effect
 

On my 400 refresh I noticed I bit of blueing at the ends of the main bearing halves where they crush together. I read something on the wiper effect years ago but can’t remember the fix. Any info or a link would be appreciated.
Thanks, B&P.

In that case if all the main Bearing and the blueing is on both haves of the Bearing incerts then the main Bores are sized to provide too much Bearing crush.

There pinching in at the parting line and reducing the needed Bearing clearance and making for reduced oil film and higher local temps.

In the least continued running will burn a Bearing!

Sounds like you need to align hone the main bearing bores. Could have been a botched prior align hone or main caps swapped from another motor and never resized.

Don't align hone to fix this issue, as that always leads to the problem of a lot of slop in the timing chain that then needs to be dealt with, you want to align Bore the mains to get the needed Bearing crush!

Bearings are made with a different shape / dimension in the parting line area so as to not have the issue that your seing taking place, so that would lead me to say that something is way off with those main journals or those are a very defective set of Bearings!