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MF 35 - Dies at Wide Open throttle

Russell Rebuilt a friends MF35 Carb, with a almost useless kit from tractor supply. I have never seen this tractor before and it had not run in a few years. So really do not know how it was running.

Other than removing all parts that were noticable and cleaning all ports and installing a few new gaskets/seals not much was done. Also did new points, condenser, plus and wires and timing. Started right up, adjusted the carb at idle and full rpm. Problem is at idle it runs best with the needle seated (all the way in), with the hand throttle at wide open main jet screw needs to be almost all the way out. This does not make sense. Setting the main needle to base and turning it out 1.5 to 2 turns it will not start nor run if you turn it to any where near this point while running. So with the settings set at where it runs best, as soon as the tractor sees extra load (hill, brakes applied lightly, tiller in dirt) and starts to loose a few rpm the governor starts to open the throttle plate as expected. As soon as it tries to open it, the tractor just dies, if you press the clutch quickly you can catch it before it completely shuts down, it starts right back up and idle fine. My guess lots of air and no fuel...WHY? I am stuck.

Jeff Z. It does sound like a fuel resrtiction somewhere in the system. First make sure you have a stong fuel supply to the carbuertor.
It sounds to me like a passage inside the carburetor is plugged.
Sometimes very hard to find and clean.

Jeff Z. I have had many carburetors with this problem.
I have replaced a few with new Zeniths.
Problems solved.

jack edward carpenter are you certain it is the carb i had a bugs wing that got into the gas line and would plug the flow of gas as the engine needed more fuel
Russell Good fuel flow at the fuel line end at car. I will recheck the float bowl level to make sure it is high enough as well. Been through the carb 3 times now and can not find any clogged ports.

The only parts to unscrew other than the choke and throttle plates were the idle needle, main jet, main fuel feed tube (takes fuel from float bowl into main airflow), needle and seat for fuel into bowl from fuel line and one small tiny jet that was screwed into the float bowl but you can not see it until the top is off the carb. Missing anything?

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