Help! I need a good mechanic!

Unless you repair the SOURCE, you will be forever plagued. Pull the tank, rinse it out, have it coated, or if it's rusted, install a new one. Clean the lines, install a new pump and filter. Even then, you may have to rebuild the carburetor again, from contamination from the tank. People always start backwards on fuel issues. You start with the tank. Or you will never fix it.