I woulda thought it would be valves due to smoke coming out of carburetor, Even when you put some gas into the engine it just starts alittle then stops over and over again
So I just recently got this old 90s ariens tiller and it will try to start if I pour gas down the carburetor, But then it puffs smoke out the carburetor and it will stop trying to start up and this will happen over and over again