1987 Toyota Tercel Fuel problem

i have a 1987 toyota tercel that stalls within 2 minutes of starting and jerks even at 70 mph. i took the air cleaner off and started it and then looked in the carb, there are 4 tubes just inside the card that come up at 45 degrees. as i watched, the 2 tubes at the rear of the carb start to fill with gas, and as it reaches the top and spills into the carb, it floods out and dies, and is impossible to restart until it has set for awhile.