Re: mercruiser 4.3 2bbl carb adjusment
Being a 4.3LX, you may have the ignition that requires it to be in "base timing" mode to properly adjust the carburator mixture. In normal timing mode, the igniton constanly adjusts timing to maintain best idle, so adjusting the mixture in normal mode may give false results. It is easy to get into base mode by jumping two wires before turning on the ignition and starting the motor. There should be a couple of guys on here that can tell the wire colors, or maybe a link to the procedure.