Mercury Marine serial numbers can be looked up on line at Webapps.Brunswick.com/literature/literatureSearch.do. Serial numbers for Mercury motors can be found on the transom bracket that came with the motor.
Serial number look-up queries for Mercury products typically divide the component into major subsystems. For example, some of the groupings included in a pull-down menu for a Mercury outboard are the crankshaft; pistons; connection rods, flywheel and stator; and gear housing and propeller shaft. The subsystem breakdown is accompanied by a schematic with labeled part numbers, making visual confirmation of the part easier for the inexperienced mechanic or the seasoned pro.