Honda Engines use a standard model naming convention.
FINDING THE ENGINE MODEL
To find the model number, look for a model number sticker on the engine.
All Honda engines model numbers start with the letter "G," such as "G100", "GX610", or "GXV160."
This is the base engine model. The engine model and serial number should be adequate for most of your needs.
FINDING THE ENGINE TYPE CODE
The engine type code is stamped into the side of the engine, usually close to the serial number. Engine type codes may be up to 4 characters. If a code is less than 4 characters, you may see asterisks as placeholders (i.e. an engine stamped with QX** is a QX type engine.)
FINDING THE ENGINE SERIAL NUMBER
The engine serial number is stamped into the side of the engine. All Honda engine serial numbers have a 4 or 5 letter prefix followed by a 7 digit number.