Charcoal Canister Delete
There are a few remedies out there if you are running extremely rich (smell that gas in the air!) or the generator simply will not turn on. One of them is to delete the charcoal canister.
For more details on charcoal canisters on gas engines in general check out this article HERE.
I had a situation where I was running the generator on a trailer AC all day in the AZ heat. I started to smell the gas in the air and after a while the generator just died. I looked online for a while trying to troubleshoot it with no luck. I cleaned and "trimmed" some of the screen on the spark arrestor. No luck. (I did completely crank the head off of one of the spark arrestor bolts because I tried to take it off when it was still very hot and just turned right off like butter. That was fun.) Checked the spark plug and it was good. No luck. Let it sit because I could still smell the gas, and after an hour or so, still no luck. The only other thing I stumbled upon was a few people talking about disconnecting the charcoal canister. I unplugged the two hoses from the left side of the canister located just above the air filter. It fired right up!
I did some more reading on it and while the generator itself is extremely good at regulating the air/fuel mixture by itself, it does not have a good way to do it with the charcoal canister installed. This causes the problems described above.
I have a diesel truck so I am fully aware of how these new environmentally conscious systems can cause a lot of unintended or unavoidable consequences.
Please let us know if this helped you out or if you have any other remedies to share!