I have had two problems with my Sears mower 4 HP easy start engine. The first is COMMOn on these engines. The hollow brass float absorbs fuel and floods floods the engine. Remove the float and examine it to see if there is gas in it.
The second problemI had was over time the main jet became completely blocked. I used a piece of wire to clean it.
By the way I have seen the leaky floats on two other engines about 3-4 years old.
1990 190E 2.6
1996 Grand Voyager 3.3
1985 Mustang GT 5.0 5 SPD
1982 Suzuki GS 750T