After 30 minutes of Running with no problems Generator shuts off with code UU. Under Voltage? It Just shuts down. Like a switch was moved. I think it's the Main/Reset toggle. Electrical side is good on power out. Right to shut off. Doesn't seem like fuel, because it doesn't hunt. Could it be exhaust Temperature? Any ideas? Appreciated. Mechanic thinks its fuel. Tanks are full of Non-Ethanol marine Gas with Stabil. Gas is 5 weeks old.