I have a case 448 a 1981 model with A MARVEL SCHEBLER CARBURETOR . i just bought it and the first day I brought it home I went to till and it started stopping and I had to restartit. I finally made iot back to my garage removed the breather and watched the carb when I tried to restart it , it would start but only run about 30 seconds and then fuel shot out the top of the carb like flooding. I took the carburetor apart and found the brass float was all caved in and checked it out in a can of gas and it sunk to bottom of can. I decided that it would be better to just by a whole kit and rebuild the fuel pump , float and needle valves. Well I have all the manuals for the tractor so it didn't take long but guess what it fires plenty of intake suction but the fuel bowl will not fill up , so I checked the fuel pump by taking the top half of the carb off and cranking to see if pump was working that was fine, checked the float settings to 1/4" and checked the float for rubbing , all things looked good but still would not start or fill the float bowl. Any body have any suggestions what I do next to get it running it is a 18hp onan. Engine sound really good when running.