IH M (1952) carburator problem

The tractor had about an inch of rust in the bottom of the fuel tank when I bought it that kept killing the engine due to the fuel tank float bowl valve clogging. I cleaned out the tank and relined it. I then flushed the fuel line to the carb. I removed the carb and cleaned it inside and out. I used my air compressor and carb cleaner to get the carb as good as I could. Next I reassembled the carb, aligned the governor to the carb when putting it back on and started the tractor. It didn't want to start until I used the choke and got it at just the right spot. It only took a couple tries to start. When I adjust the idle screw, high speed screw or governor screw the tractor responds in the anticipated way. The problem is that if I fully release the choke the tractor dies. It responds the same if I fully open the choke. The tractor runs great if I leave the choke at about the halfway point. This would be fine if the weather never changes but winter will come again in Northern IL. Does anyone have any ideas for me to try? Any thoughts would be appreciated.

Thanks in advance!

Thanks.

There was so much rust in the tank that I had to get rid of the big chunks. First I used drained as much fuel out of the tank as possible. I then left the tank off the tractor and open for awhile in order to make sure there wasn't a lot of residual fuel in the tank. (evaporation) Next I used a hot steam pressure washer to flush out the tank as much as possible. The pressure washer helps because the baffle in the tank can make it near impossible to flush out everything. I then drilled a hole in the rear, lower, bottom portion of the tank (pointed end at about 45 degree angle if the tank was level as it would sit on the tractor), that I would be able to weld a NPT threaded insert into at a later time. (This becomes important in the coating and etching process later.) I purchased a NPT plug and fitting at the local farm store. After drilling the hole I again pressure washed the inside of the tank and the hole allowed the tank to drain out. After getting all of the rust and gunk out of the tank I then welded in the fitting for the threaded plug. I wanted to make sure the tank was real clean so I used a 50/50 mix of muratic acid and water to clean and etch the tank. I put the plug in and rotated the tank at different angles and let it sit for awhile to dissolve any rust on the walls inside the tank. After I was satisfied that the tank was clean inside I drained all of the fluid inside the tank. The tank will begin to rust inside almost immediately after you drain it so you be ready to coat the tank insides almost right away. Before coating the tank inside there is one other thing to do. (especially because an M tank has a seam along the inside) The next step is most often forgotten by many doing their fuel tanks. You need to make sure the tank is dry with no muratic acid to continue eating away at the metal seams. I use a torch to lightly heat the seam along the outside of the tank to dry any moisture. I don't want to have the sealer cover and seal into the seam any water or acid. Once the inside of the tank is very dry use a tank sealer to coat the inside of the tank by putting plenty of sealer in the tank and rotating the tank around to slosh the sealer all inside on every sidewall. Depending on the size of the fuel tank you are doing you will be able to drain the sealer out after coating all sides back into the original cans and save it for another tank later. You can remove the plug from the fitting that was welded on in order to drain the sealer. I leave the tank to dry and then recoat the tank several times until I am satisfied that there is sufficient coating. Depending on the sealer that you use (it can be purchased at most automotive supply stores) you will need to give the tank ample time to dry before putting it back on the tractor for use. Good Luck If you have any questions reply to this response. I'll check it.