When you say seized do you mean it locked up while running, or mean it won't turn over when trying to start. If locked up while running you are done. if it won't turn over to start then remove the spark plug and allow the gas to drain from the cylinder, and turn over the engine by hand to push out more gas. or blow out the cylinder with compressed air. DO NO CRANK THE ENGINE TO EXPEL THE FUEL FROM THE CYLINDER, doing so can create static electricity which can ignite the fuel. The repair the carb, and drain and change the oil and filter.
