Some think it is "overkill" but here's what I do.... I was having problems with carb diaphragms going bad in as little as 4 to 6 weeks. I don't know if it was my fuel source(s) or what, but I had a run of bad luck with carbs, whether I ran them dry or left them full of gas. So, I started using what I call "Storage Fuel". It is Coleman Camp Fuel, with Sta-Bil added, and 20 to 1 oil mixed in. After I am done flying for the day, I drain my regular fuel out of the plane, fill the tank about half full of the "Storage Fuel", and run the engine long enough at various throttle settings to be sure the fuel has gotten all through the carb and engine. Then I choke the engine to kill it, and store the plane. No carb problems since....

AV8TOR