Yamaha EF2000iS Generators

I pulled the plug again and it's actually running lean, makes sense with stumbling. I cleaned the "muffler" out. Opened the screw drained the fuel out. Took air cleaner off, put some Seafoam in carb. Fired it up, still rough. I moved the on/off gas cap switch as I've read that it opens more half closed, didn't work. Only thing that smoothed it out is half choke. I've probably read 500 threads on this issue and only one other guy had that issue with half choke. He even took it to the dealer and they couldn't figure it out? It's cool in livermore this weekend so we don't need the ac and we have enough propane to run the fridge. Wife needs it on for coffee. I've read where guys do all this stuff, modifying, using jet fuel ! And draining after every weekend out?? This isn't an old Coleman here, it's a $1000 Honda. I'll take the inline filter off (find YouTube how to get to it). If it's clear, I'm not taking the carb off. If this was a year old or I didn't maintain it, I'd understand, It's not. If this doesn't work I'll be returning both.

Thanks