I have about a 15 year old Troy Bilt 5500 watt generator. Hardly gets used and is reliable and runs great. Running it today during an outage I was doing a voltage check and I am only getting115 volts. I would like to get at least 120 volts. I can do this by pushing on the governor and speeding it up just a bit. Is there any way that I can permanently adjust the speed up a little?