I have a 2000 Sportster 1800 with a 210hp Mercury V6 engine. The engine at idle runs rough and smokes more than I've seen from other SeaDoo boats with simular engines. Advancing the throttle the engine seems to smooth out with virtually no smoke. Question...should I have the carbs adjusted, rebuilt, or sync'd? I don't think its electrical since it runs like a champ above idle. Any help would be appreciated.