I have an old Johnson model number TD20, serial number 69694, 5 hp, 1946 approx. The carburator leaks like a sive. I replaced the gasket on top of the carb and the gasket between the carb and the motor but to no avail. The gas comes out of hole on top of the carb above the float. If I shut off the gas it stops but then if I open the needle valve it starts to leak from a large silver screw on the bottom. Seems to me like the float might be stuck or not operating properly but I can't figure out how to get it out. Any suggestions?<br /><br />Thanks<br />KLC