I have a 454 merc with a rochester 4 barrel. I recently posted a problem with the carb and adjusting the throttle cable gave me more rpms. The marina tells me I need a new carb sincce my secondary barrels are not opening. <br /><br />I looked in the carb and noticed the bottom plates on the secondary barrels open mechanically.<br />However the top plates stay closed. I assume it is vacumn operated. <br /><br />Is there anything short of a rebuild that I can do to get by for a bit. I am converting my boat to fueld injectio and I would like it to get by this season. The boat doesn't have any power until I get it up to 3800 rpms to get on plane.it would get over the hump at 3200-3300 hundred before