My generator is not running properly for the last few days. It starts off fine for about 20 minutes and then revolusions go up and down in a wave pattern which gets worse and sounds like it's going to stall but it hasn't stalled yet. When I turn it off there are no fault messages. I've changed the primary and the Onan fuel filter and that hasn't fixed the problem. It doesn't really sound like fuel starvation as the ups and downs are too even for that.
Has anybody got any suggestions what I could look for? Many thanks.
