Drive around and snag a push mower that is on someones curb. Run all the Seafoam you want in it. Pull the head. Take pictures of all the carbon that is still in there and behind both valves.According to Project farm and Chris Fix Videos it does help. It will not do it 100% in one tankfull but it does have some impact after one tank
Bet you put seafoam in your cornflakes LOL. So $5.00 a gallon for gas. $8.75 for a tiny can of kerosene. Man you spend some cash on lawn mower fuel.