This document pertains to the Volvo AQ125B, a marine propulsion engine. This engine features an inline 4-cylinder configuration with a displacement of 2.3 liters (2300cc) and an approximate power output of 141 HP. Typically equipped with a carbureted fuel system and water cooling, the AQ125B is known for its robust construction, often utilizing a cast iron cylinder block, and its reliable performance in marine applications. This Workshop Service Repair Manual provides comprehensive information for the maintenance and repair of the Volvo AQ125B marine engine. It covers essential procedures, technical specifications, and troubleshooting guidance necessary for owners and technicians. The manual details lubrication requirements, filter types, ignition system information, and other critical aspects to ensure the longevity and optimal functioning of the engine.