Leaderboard

Have you tried blowing out the line from the carb end, to the tank?

Sometimes people think they've cleaned, and /or rebuilt a carburetor, only to find out it didn't take. Those things have tiny little fuel passages that can easily be missed. That's why I suggest you let the fuel do the cleaning, using an additive. Sometimes that isn't possible, but I think it'll work here. Assuming that's the problem. If it's the tank, you could draw some gas through the line, into a glass jar. Look for impurities, also make sure there's good flow. Or it could be the gas cap vent. When the engine is having issues, quickly pop the cap, look for immediate improvement. Verify by driving it awhile with a rag or something stuck in there. No problems, then replace the cap. See what happens, then repeat till you know for sure.