1973 john deere 300 carb issues

Hi Im new here. I just bought a 1973 john deere off a buddy for cheap. However when I got it there was no carb so he gave me one for it. I just took it not thinking much of it. Well he gave me a tillotson HD 106a. off a 440 sno jet. I put the carb on it and hooked up all of the lines. I can get it to run however the throttle seems touchy and it want to flood out. If I take the fuel line out of gas it will run for 20 seconds or so. So I guess my main question is is this a suitable carb for this sled? or should I be tracking down a walbro that came on it? I dont know much about these old sleds or about diaphragm carbs. The motor is a 290. Thank you for any help

1973 john deere 300 carb issues