Mr Wizard's info is pretty much correct. If you are getting 20vac at 30amp gen receptacle, then most likely a "field" problem. Even at only 200 hrs, the field brushes might be sticking in the holder, or the slip rings are oxidized or dirty. possibly a control board going bad, as the field (voltage regulation) is part of the control board. Unfortunately, brushes/slip rings are not easily accessible, as they are located behind fan/flywheel assembly. there are troubleshooting procedures to determine problem, but some specialized test equipment needed. BTW, no low oil level switch is used on this spec 4KY.
