If I can't clear the ports using a welding tip cleaning wire, carb cleaner, and an air blower, I fire up my steam cleaner. I use that steam cleaner for everything around the shop and house. It's one of the best tool investments I've made. However, ethanol gas may have not only gummed up the ports with fuel varnish, they may actually be corroded shut with metal oxides too. I have a small set of micro bits that are good for clearing corroded jets but they won't bend around corners. If a replacement carb is less than $20 I usually just toss the old one in the spare parts bin and order a new one as the Welch plugs are going to cost half that much unless you have enough need for them to buy them in bulk.