I'm not the best at knowing what the parts are called, but a tech once shared the best knowledge of how to maintain your generator. I use this not only on the on board one's on my trailers, but I use them on the 2 I have around the house. The Onan on the trailer gets cycled almost every weekend. The house generators usually every 3 or 4 weeks. This is what I was told to do from the tech.
1. Start the generator and run it without a load for 5 to 10 minutes. This allows something to do with the magnets on the generator to sync.
2. Then put moderate to heavy loads on the generator for about 10 or so minutes.
3. Then take the loads off, allow the generator to run for another 5 to 10 minutes. This allows the magnets, or whatever they are called, to demagnetize.
Again, not sure what the tech terms are called, but I have done this for years and have never done anything to my generators except change the oil.