Stop the fuel flow to the carburetor either turn off the fuel valve or pinch off the line with a pair of fuel line pinch off pliers or a pair of vice grips.
Small generator engine surging.
If your generator is surging at idle then likely this small hole is either completely plugged or very restricted.
Failing capacitor or other components.
This is for bowl type carburetors only.
Signs of surging include.
Issues causing generator surges.
A surging generator is an indication that there is something wrong with your equipment.
There are actually numerous causes for generator surging including.
Partial blockage of main jet.
To clear out the whole simply take a single wire from a steel brush or burn the paper or plastic off of a twist tie that you would use for a loaf of bread and use the inner wire to run through this hole several times and remote.
Incorrect fuel use fuel levels and fuel quality in gas oil generators.
Your generator was designed to utilize specific fuel sources and anything else may cause problems in operation and irreparable damage.
Engine will run but it surges hunts for a constant rpm 1.