I have a Kohler ch25s. This engine has 2400 hours. I feel great about it lasting this long practically problem free. My dad has been using this mower for the past several years on his property. Earlier this summer it bent a push rod on#2 exhaust valve. It sat summer before I had time to mess around with it. I replaced both valves (and lapped) went ahead and replaced the hydraulic lifters also new head gasket. Put new spark plugs in it and started it up. Now it is running rich both plugs are black soot and dry, while running a hint of black smoke is noticeable through exhaust. Smell is very rich. Put inline spark testers on both plugs. Both plugs have a steady bright light. I took off carb bought rebuild kit cleaned carb and still running rich. One thing I noticed while running I can push down the accelerator pump and it seems to smooth out not sure what that means if anything. I have done everything I know to do. Is my carb bad? I don’t mind replacing it just trying not to throw money at it with exhausting other options. What do you all think?