A closer look at the front throw, although it measures fine, shows a darker spot, about a 1_4" wide running about a 1_4 of the way around in the center. Would this be anything to worry aboutIJ
I'm not sure about n6 but we had a ballancer problem on a 7045 that really pounded out n1 rod bearing. It started with breaking alternator brackets,then alternators and ended with a knock in n1. The bearing turned in the rod so the thin side was on the bottom and the piston contacted the head. The ballancer appeared ok except the timing marks didn't line up.
Make sure you check the rods .I have had rods shrink.That will not let enough oil in which will increase wear and heat.The heat will be greater closes to the crank,drawing the metal in.That is what made the bearings loose in the rod.Sounds crazy but I had it happen on my 8050.
Is that the deal where the rubber breaks and the outer weight starts turning around the inner hubIJ I noticed minor vibration and mentioned it to the service manager who said to replace the vibration damper. Maybe I was luckier than others. Tom in MN
Yes it is. Apparently bad ones set up a vibration that can break through the oil film. Also most manufacturers have hours at which they need to be changed. Some say 2500 hours.