I meant to type VOLUME above not value.
My guess is that black oil splooge garbage was some kind of break in lube and a LOT of it.
Was the unit new with no gas in the tank? I don’t remember experiencing that on a new engine, but I guess if it stops and goes away, you should be good. I’d find something to clean that’d take 20 minutes or so just to see.
I have a cheaper model that I believe said to run the original oil for 5 hrs. I imagine break in takes about that long so hopefully the issue goes away in that time.