The problem is the capacitance of the generator ( it seems to be an induction generator), also it seems that the capacitance changed in value.
Some gas generators may have a frequency circuit to set the frequency right and the voltage output be as well regulated with a cheap circuit using a Triac that may be stuck high giving the 165 volts.
Ask Coleman about the problem and tell them the gen is far away so you need the info.
Regards
Nando