I bought a small inverter generator, filled it with SAE10-30 oil that shipped with it, taking care to check with the dipstick several times so as not to overfill it (though it did take the full bottle), and then ran it for 5 hours, varying the load, per the manual's instructions. The jar in the photo shows the oil that came out afterwards. Is oil normally that dirty after the initial break-in of these inverter generators?
Yes.
Many engines are lubricated with a "grease" or heavy oil which is designed to stick to the machined surfaces until they are properly run for the first time.
You followed the running-in process and this is designed to "flush" that original oil or grease and allow the parts to "bed-in" as well. Most times as bearings, rings etc wear-in there is metal residue that is caught by the filter as part of the running-in process.
So that oil you show looks about right. If you are really concerned then send a sample for testing and send further samples after every 10 or 50 hours of running. Chart the progress of the impurities.
