Using WD-40 to clean a carburetor can be an effective way of removing stubborn dirt and grime build up. The product is designed to penetrate hard-to-reach places, which makes it ideal for cleaning the narrow passages and crevices of a carburetor. To use WD-40 on a carburetor, start by disconnecting the battery and removing any air filter or intake system components that are blocking your access to the carburetor. Then spray WD-40 into all of the openings, making sure that you evenly coat each area with enough product so that it can penetrate deep into the crevices where dirt may have collected. Allow this first application of WD-40 to sit for about 10 minutes before using compressed air or a soft brush (like an old toothbrush) to dislodge any remaining debris from inside the carburetor body itself. If necessary, repeat this process one more time with another application of WD-40 before wiping away any excess liquid with a rag or paper towel. With regular maintenance and periodic cleaning using WD-40, your car's engine will run smoother than ever!