Identifying your Mercury outboard motor can be challenging, particularly if your motor was built prior to March of 2001. If your motor was built after March 2001, the identification is significantly easier since there's only been one change in the method of developing model codes for new products, and that change--adding a consumer-readable date to the information on the motor--makes it less difficult to identify the latest versions of Mercury outboard engines instead of just depending on the logo on the engine cover.