Honda outboard motors have been in production since the 1960s. While a variety of engine types have been produced in this period, the models all share a standard method of identification, in the form of their serial number code. This makes it possible to identify how old a Honda outboard is with the serial number.
Examine the mounting brackets of your engine. The serial number, also called the model number, is printed on the left bracket when viewing the motor from outside the boat. The serial number is made up of a string of between nine and 11 letters and numbers.
Ignore the first couple of letters, which will be "BF", as this is the code for "Honda" and therefore demonstrates that the engine is actually a Honda outboard. Ignore the next two digits, or three digits if the third digit in the series is a "P", as these represent the horsepower of the engine. The "P" indicates that the propeller is a "high thrust" model.
Note the next two digits, which will be either a letter followed by a number or two letters. This is the code for the year of manufacture. If the second digit is an X or a Y, the engine was produced in 1999 or 2000 respectively. If the second digit is a one, two or higher, this represents the year of production in this millennium. D1 indicates production in 2001 while A3 indicates 2003.
If the serial number on the left mounting bracket has become unreadable over the years, there is a second number printed onto the engine. This frame number is located near the transom, on the side of the engine shaft housing. It will provide the same information as the model number but is slightly harder to get access to.
Before examining your outboard for the model number, ensure the engine is turned off and cannot be started accidentally. Engines are dangerous equipment, especially when they are attached to a propeller that could begin spinning at high speed if not turned off completely before examination of its housing takes place.