Genset was not overfilled and yes it has oil in it. It has been leaking for 4 years and I check it all the time. I posted this to possibly help others with the same problem. I switched to syn 10-30 in the MH at about 50k miles, the tow car at about 70k miles. I figured I would just buy one oil for all three engines including the genset. The MH now has 107k miles on it and never leaked. The tow car 2002 Toyota Corolla leaked right away at the pan gasket. I tightened the pan bolts 3 times before I got the leak to stop. The genset leak did not show up until a year after I switched to syn because it gets used minimally. I could never find the leak and was not about to pull it out and spend another $1000 to fix it as Mr Wizard said. I am just happy it was an easy fix.