This service manual covers Mercury OptiMax outboard motors, including models 115, 135, 150, and 175 horsepower, manufactured from the year 2000 onwards, identified by serial number OG960500 and higher. These engines feature Direct Fuel Injection (DFI) technology, CDI ignition, and water-cooling systems, designed for reliable performance in various marine applications. The robust engineering of the Mercury OptiMax series ensures durability and efficiency, making them a preferred choice for demanding watercraft operations. This comprehensive English-language manual provides essential information for the repair, service, restoration, maintenance, rebuilding, and diagnosis of your Mercury OptiMax outboard motor. It includes step-by-step instructions, a troubleshooting guide, and detailed technical specifications to assist owners, mechanics, and technicians. The manual emphasizes preventative maintenance and offers guidance on specific service intervals, ensuring your engine operates at peak performance and longevity.