This manual covers the Volvo AQ105, a 2.0L 4-cylinder gasoline engine with an approximate power output of 121 hp, designed for marine applications and typically paired with an inboard drive unit. Known for its robust construction and reliable performance, the AQ105 engine is a testament to Volvo's engineering quality, providing dependable power for various watercraft. This engine utilizes a water-cooled system and is built for durability and efficiency in demanding marine environments. The purpose of this Service Repair Manual is to provide comprehensive guidance for the maintenance, repair, and servicing of the Volvo AQ105 engine. It details essential procedures, technical specifications, and troubleshooting steps for common issues related to carburetion, ignition timing, and cooling system performance. This manual is an indispensable resource for owners, mechanics, and technicians, ensuring the optimal operation and longevity of the AQ105 engine through accurate and detailed information.