We have a 7500W "lug about" generator that we connect to our country stick house. Approx 4 times a year (for the last 3 years), we simply connect its output and use it. For the last few times, I've noticed our generator was louder then usual. But, didn't think nothing of it. Last night (while using the generator during a 3 hour black out), our home's dimmer light switch was "all the way down" and the light was still on. WOW. Much brighter then I remember - when using regional grid power.
Today, I took my low cost hand held Volt Meter and tested my home's kitchen outlet. Display solid at 119 Volts. Between 110 - 120 is perfect. I started my generator and tested its outlet and to my surprise, 146 Volts. WOW - way too much volts. I took a little screw driver and turned down its gas engine RPM. Simple 1/4 turn on its idle screw. Now, output of the same generator outlet is between 116 - 122 Volts (since engine RPM isn't 100% constant). And, its gas engine is now much quieter as well.
If you have a generator for your stick home or RV, do test its output AC range as well. Simple low cost volt meter (re: https://www.northerntool.com/images/p.../163100_lg.jpg
) works great.
Hope this helps others...