This comprehensive workshop repair manual is specifically designed for the Mercury Mariner Outboard 135 HP DFI Optimax models produced between 2000 and 2005. Meant to assist both novice and experienced mechanics, it provides detailed instructions and diagrams for troubleshooting, repairing, and maintaining your outboard motor. The manual covers a wide range of topics essential for understanding and working on your engine, including: * **General Information and Specifications:** This section provides vital information about your motor, including key specifications, important safety precautions, and overview of its components. * **Maintenance:** It outlines a comprehensive guide to routine maintenance tasks like oil changes, filter replacements, and other regular servicing procedures. * **Outboard Installation:** Detailed steps and instructions for installing the outboard motor on your boat, ensuring proper fit and function. * **Electrical System:** Covers all aspects of the electrical system, including wiring diagrams, troubleshooting guides for the ignition system, charging and starting systems, and detailed explanations of electrical circuits. * **Fuel System:** Provides a in-depth explanation of the fuel system, encompassing the fuel pump, direct fuel injection system, and oil injection system. * **Emissions:** Get a thorough understanding of the emission controls and their proper operation. * **Powerhead:** Detailed information on the powerhead assembly, including disassembly, inspection, repair, and reassembly procedures. * **Cooling System:** Learn about the cooling system, how it works, and how to diagnose and fix any cooling issues. * **Mid-Section:** Detailed instructions for working on the mid-section, including disassembly, component inspection, and reassembly. * **Clamp/Swivel Brackets & Drive Shaft Housing:** Provides information and instructions for working on the clamp, swivel brackets, and drive shaft housing components. * **Power Trim:** Covers the power trim system, its operation, troubleshooting, and repair procedures. * **Gear Housing:** Detailed guides for working with the gear housing, including disassembly, component inspection, and reassembly. * **Right Hand Non-Ratcheting and Left Hand Non-Ratcheting:** Detailed information for working on the right and left hand non-ratcheting mechanisms. * **Attachments/Control Linkage:** Includes instructions for working with all attachments and control linkages. * **Color Diagrams:** Enhanced understanding with the use of detailed color diagrams that illustrate various components and systems within your outboard motor. With this manual, you'll have a comprehensive guide at your fingertips for tackling any repair or maintenance project on your Mercury Mariner Outboard 135 HP DFI Optimax.

The Mercury Mariner DFI Optimax 135 HP outboard motor, produced between the years 2000 and 2005, marked a significant advancement in marine engine technology. This powerful and efficient engine, designed for recreational boating, featured Mercury's innovative Direct Fuel Injection (DFI) system. This cutting-edge technology, unlike traditional carburetors, directly injected fuel into the combustion chamber, resulting in precise fuel metering, increased combustion efficiency, and reduced emissions. The Optimax 135 HP boasted a remarkable power-to-weight ratio, enabling it to deliver impressive acceleration and top speeds while consuming less fuel than its carburetor-equipped counterparts. This engine was renowned for its smooth and quiet operation, thanks to its advanced internal components and noise-dampening technologies. The Mariner DFI Optimax 135 HP was a popular choice for a wide range of boats, from fishing and cruising boats to smaller runabouts and dinghies. The Mercury Mariner DFI Optimax 135 HP's reliability and performance were further enhanced by its robust construction and advanced engineering. The engine featured a durable and corrosion-resistant aluminum alloy block, a lightweight and durable composite design, and a precision-engineered crankshaft and connecting rods. Its integrated electronic ignition system provided consistent spark and optimal combustion, ensuring reliable starting and smooth running. The engine was also equipped with a multi-stage oil filtration system, guaranteeing optimal lubrication and extending engine lifespan. The DFI system contributed significantly to the engine's longevity, as its precise fuel injection minimized wear and tear on internal components. This engine's combination of power, efficiency, and reliability made it a sought-after choice for boating enthusiasts seeking a high-performance outboard motor that could withstand the demands of recreational use.