Briggs and Stratton 550ex Plastic Carburetor Cleaning

These are my favorite carburetors to clean! The needle and seat almost never leak, they rarely need any new parts, they have a near 100% success rate, and, to top it off, when you get good at it you can do one in about 15 minutes! The biggest issue with these is that they have a tiny main jet that has very little tolerance for the little gel beads that form in fuel in the bowl after sitting for the winter. 99% of the time I find that to be the only clog. It is very important to wipe the inside of the carb and blow it out with compressed air so you don’t leave any gelled fuel behind to immediately clog it again. Have fun!

[@mlhm5]

You can clean the gunk in the main jet as many times as you want, however, it will stop up again and again because the federal government wanted fuel efficiency and as a result the opening in that main jet is 0.12-0.13" in diameter (this where all the gas to the engine must pass through). You need to drill out the main jet to .021" to make sure it does not clog up. This is the diameter of most small engines without the plastic carb and it works just fine and even better at .021".