Flooding is caused by fuel either getting by the needle/seat assembly or around it. Make sure the seat asembly is sealed at the gasket under it. Also check the float level and float travel to make sure it isn't hanging up on anything.
If you have the capabilty, let the carb go dry then re-fill. Do this by shutting the pump down and running the carb till it's empty. You must cylce the pump when the carb is refilling, as it is possible for an electric pump to fill the bowl fast enough to hold the float down on the first start-up. Letting the carb go empty then re-fill will usually wash any debris off the needle if something has found it's way between the parts.....Cliff
