Locate the identification plate or sticker above the waterline on either the port (left) or starboard (right) side of the outboard bracket. Photograph the plate/sticker or record its information for easy reference when ordering Yamaha replacement parts.

Your Mercury outboard's serial and model numbers are located on an identification tag affixed to the mounting bracket. In some cases, this information may also be found on the fly wheel cover of the engine. 

Engine Serial Number: Located near the starter on the flywheel housing, rocker arm cover, or flame arrestor cover.

Sterndrive Serial Number: Located on the starboard (right) side of the upper driveshaft housing or on the back of the housing.

Transom Serial Number: Located on the upper part of the transom assembly.