Yanmar 4JH3-DTE – Inboard Marine Diesel Engine 125 HP

Yanmar 4JH3-DTE 125 HP – Legendary Mechanical Turbo Diesel

Solving the complexity issues of modern electronic engines, the Yanmar 4JH3-DTE delivers 125 HP at 3800 RPM through a robust, mechanically-governed design. Highly sought after for repower projects in the USA, this high-RPM diesel provides the “punch” needed for fast-planing hulls and heavy-duty auxiliary use on performance sailing yachts. Its narrow profile and mechanical reliability make it a favorite for American boaters who prefer a dependable, high-output engine that is straightforward to maintain in remote coastal areas.

Meeting applicable USA EPA standards for its class, the 4JH3-DTE emphasizes mechanical longevity and high power density for the American recreational market. The engine’s direct injection and intercooled turbocharger ensure a clean, efficient burn, providing US boat owners with a refined power plant that thrives under high-stress operation. The freshwater cooling system is built to Yanmar’s rigorous maritime standards, ensuring that internal components remain protected from the high-salinity conditions common in American coastal waters.

Core Technical Specifications

• Maximum Output: 125 HP at 3800 RPM.
• Displacement: 122 cubic inches (2.0 Liters).
• Configuration: 4-cylinder in-line, water-cooled diesel.
• Aspiration: Turbocharged with seawater intercooler.
• Dry Weight: Approximately 520 lbs with gearbox.
• Electrical: 12V / 80A marine alternator standard.
• Fuel System: Direct mechanical injection.
• Bore and Stroke: 3.31 x 3.54 inches.