I'm the new owner of a pristine 1997 1800 center console power by Yamaha 115hp 2stroke with a Yamaha 4hp kicker. Boat was just serviced and look and runs great. Have a simple question regarding the choke. Two push/pull buttons are located on the console. The upper one appears to be the choke for the main motor. I can't for the life of me figure out the lower one. Probably also related to the choke but don't know how. Any takers?