This manual covers the Mercury 18HP / 25HP Outboard Motor, a 2-stroke engine designed for marine applications. While specific production years are not detailed, this engine series is known for its robust construction and reliable performance on the water. It operates on unleaded gasoline mixed with oil and features a CDI ignition system for efficient combustion. The engine provides either 18 or 25 horsepower, suitable for a range of boating needs. This owner's manual provides essential information for operating and maintaining your Mercury outboard motor. It details critical maintenance procedures, including lubrication and cooling system care, alongside technical specifications and troubleshooting guidance. By following the instructions within this document, owners and technicians can ensure the longevity and optimal performance of the 18HP / 25HP outboard motor.