CHDinCT
Veteran Member
Those older Briggs do not like Ethanol. I have a walk behind DR string trimmer with one on it. The seat for the float is some sort of gasket material that turned to mush. As it did the engine did the same as yours, most likely from getting too much gas. That shouldn't be an issue with a new engine that's designed to run with Ethanol in the gas.
You're probably right. Problems started a few years back when I somehow stored it for winter with gas in it. I'm always careful to run the gas out of the carb whenever I'm done with it but somehow I forgot that year and even though I use stabilizer in every tank of gas, it messed up the carb. Ran some Sea Foam through it which helped some.