Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Hi Engine-Man,
I have the IR31 Shovelhead. I bought the new cam thinking it would idle better. The first tank of fuel it ran great. After the third tank it quit running. I discovered the lobes were wiped on the new cam. Too soft maybe? So after cleaning out all of the debris in the cavity I put the original cam back in and with much frustration and work it seems to be running on both cylinders for now. I’ve found the valve clearance is pretty critical. About a 1/2 mm seems about right. And the carb is extremely touchy also. So disappointed about the new cam.