I have been having an issue with my 1600 all spring. If I take off to fast it will die but it seems like it wont do it if I pull the choke out a little bit. The issue comes and goes, but seems to get worse as the engine warms up. Also if I rev the engine up to fast it will stumble once it reaches full throttle, and it takes it a minute to recover. It will do the same thing when I upshift the hydra-power. Lastly, when I was using it to disk every once in a while when I turned around on the end and started heading back across the field, it would start to gallop really bad when I hit the throttle or shifted the hydra-power, and the only way I could get it to quit was to idle it down and slowly rev it back up. Everything in the ignition system is new, and the carb has been rebuilt. We have checked the timing, tried adjusting the carb, and replaced the coil but nothing has eliminated the problem. I should mention the we did a complete out of frame overhaul on this tractor last winter. I have a really hard time thinking it is a fuel issue because it doesnt lack any power, and will still pull like an ox. About the only thing we havent checked is the governor. At this point we are stumped, what are your thoughts?