do you know how to check for the error code? the flashing light?
I've never personally seen a code flash that was helpful the times I've had generator issues, but maybe that could help you clue into what it is.... maybe.
I've this a lot, that the pumps are often an issue with these things...but it doesn't make sense to me that the thing runs but won't start. I think if it was filter or pump it would struggle when running.
the filter, especially, but also a weak pump would cause problems when it's running under load (flow rate is higher)
I'm leaning to a carburetor issue. One of the jets maybe plugged up a bit.... like an idle jet? maybe the sea foam trick would work???
Not saying that this would help your issue....Once, my generator started surging. I found that if I turned the altitude screw full way, I think to the high altitude direction, it would smooth out. I turned that thing back and forth a few times while it was running, might have let it run a bit while it was in a smooth adjustment, and then corrected for the right altitude and the thing has ran smoothly ever since...
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