Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Welcome to JUST ANSWER small engines, let me try to help you !! I don't know it all, but maybe together we can get you a satisfactory answer!
Make and model? Fuel, gas or lp? Engine make and model? Single cylinder or twin? Do you have spark at the plug?
If you have fuel coming out the overflow on the carburetor, the carburetor is flooding the cylinders. Shut off the fuel and see if you can get engine to run. Sounds like the needle valve in the carburetor is stuck.