MF 230 Fuel Issues

chelton1 · Jul 7, 2025

I have an MF230 gas tractor with the Continental 4-cylinder engine. It has been a good tractor but I've had chronic carburetor issues for several years. It has a Zenith carburetor which I rebuilt multiple times over the years. Last fall I replaced the ignition system with an electronic ignition, including new plugs, coil, spark plug wires and ignition switch. I finally replaced the carburetor with a rebuilt Zenith of the same model, when I kept have problems with gas leaking from the float bowl into the air intake chamber. The new carb has and adjustable jet on the float bowl, which has greatly improved its performance. It runs and idles great for about 30 minutes and then sputters, forcing me to pull the choke to keep it going. This continues the rest of the time with the intervals of sputtering become shorter unitl it eventually dies. I will re-start, but continues the same way. Frustrating as hell!

A fellow blogger had mentioned earlier it could be a vacuum lock, but I loosened the gas cap when it started but no improvement.

Any thoughts or suggestions would be greatly appreciated.

Thanks!

JWR · Jul 7, 2025

chelton1 said:
I have an MF230 gas tractor with the Continental 4-cylinder engine. It has been a good tractor but I've had chronic carburetor issues for several years. It has a Zenith carburetor which I rebuilt multiple times over the years. Last fall I replaced the ignition system with an electronic ignition, including new plugs, coil, spark plug wires and ignition switch. I finally replaced the carburetor with a rebuilt Zenith of the same model, when I kept have problems with gas leaking from the float bowl into the air intake chamber. The new carb has and adjustable jet on the float bowl, which has greatly improved its performance. It runs and idles great for about 30 minutes and then sputters, forcing me to pull the choke to keep it going. This continues the rest of the time with the intervals of sputtering become shorter unitl it eventually dies. I will re-start, but continues the same way. Frustrating as hell!

A fellow blogger had mentioned earlier it could be a vacuum lock, but I loosened the gas cap when it started but no improvement.

Any thoughts or suggestions would be greatly appreciated.

Thanks!

I think you have a float sticking in your carburetor. I had that same set of symptoms on a 1954 Massey Harris Pacer. [Actually I'm leaning on it in the avatar to your upper left of this text...] Four cylinder Continental engine of course though smaller than yours. When I was a kid 65 or 70 years ago I used to stand up and whack the side of the carb (which I could barely reach with a wrench from the driver's seat) to jar the float loose and it would run normally until the float stuck again. I rebuilt it multiple times and that did not fix the issue. I am not a fan of additives in general BUT I started using gasoline additive (Seafoam) in later years and the problem disappeared. Recommend trying it. I never could figure out what was causing the float to hang up.