Yamaha V8 XTO, the redefinition of offshore
Yamaha launched its new V8 XTO Offshore, a 5.6-liter 312.6 kW engine, with a compression ratio of 12.2: 1. V8XTO is the result of a massive redefinition of the concept of “offshore engine” and is backed by Yamaha’s years of experience in the industry. The V8XTO has double overhead camshaft for each line of cylinders. The camshafts are connected with a self-regulating chain immersed in an oil bath to obtain a more precise timing. The valves, coated with carbon, guarantee a longer life.
Among the innovations that Yamaha has introduced, there is a fully integrated power supply system. This gives its best especially in combination with Yamaha’s Helmmaster integrated boat control system. The innovative joystick, that eases maneuvering and anchoring, and the CL7 color display enrich the package. The V8 XTO Offshore is the only 4-stroke direct injection offshore engine.
The direct injection system includes five fuel pumps and generates injection pressures up to a maximum of 200 bar. The injection system is on three levels and uses a vapor separation system (VST). It has two independent fuel pumps that are activated at different engine speeds. The combination ensures greater accuracy in flow and delivery, even at maximum rpm. In addition, the In-Bank discharge function provides a direct path for the gas to the bottom unit and outside through the propeller hub, improving flow. This means optimizing combustion at each burst and obtaining more power.
Yamaha V8 XTO 360-degree optimization
The design optimization also involved water pumping. The V8 XTO features a unique two-stage water pump and a double chamber oil pump, both designed to operate at high rpm. The first is equipped with a rubber impeller with an ultra-resistant steel seat to generate high pressures. The volume of cooling water that the system provides guarantees precise temperature control even in severe conditions.
The optimization also involved the gearbox, which now is more robust, with reinforced gears. The technology of the plasma casted cylinders guarantees the compactness and durability of the V8 XTO. Even the micro-texture of the surface, 60% more resistant than steel and much lighter, increases the compactness of the engine without compromising its performance. The lower friction of the surface also helps to optimize fuel economy.
Moreover, Yamaha also improved the V8 XTO’s wheelhouse, to make it a unique offshore engine. In fact, it is electronic and completely integrated. There are no hydraulic connections and the response is faster and smoother.
Talking of propellers, the XTO V8 mounts the exclusive XTO OS. Their design ensures that the engine expresses its full torque potential. The structure of the blades is innovative and, featuring a greater surface, they can easily move large boats too. Moreover, they guarantee more thrust both directions of movement, with diameters between 16 and 17⅛ inches. Still in terms of maneuverability, the propellers take advantage of the new exhaust system that allows them to “bite” clean water in reverse. So, this results in the production of a reverse thrust three times higher than that developed by Yamaha’s F350.