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Tuesday, November 19, 2019 

UK company Cox Powertrain says that production of its high-powered diesel outboard, the CXO300, is imminent, following 11 years of development and establishing a new test and assembly facility on the UK south coast with an investment of 80m.

Cox says that its 300hp diesel outboard is the first purpose-built diesel outboard designed from ground-up. On-water tests have shown it offers 25% better range compared to a gasoline outboard and is designed to last up to three times longer, as well as offering significantl;y higher peak torque at the crankshaft.

“We are doing something new, so we have to be particularly thorough in our early stage testing and engineering,” said Vince Parry, Cox Powertrain’s Principal Engineer. “We are not just iterating a product. Instead of taking an engine made for use in cars and motorbikes and simply adapting it for marine use, Cox’s team has succeeded in creating this unique engine by starting from the ground up to design a marine diesel outboard. We take the best of marine and combine it with the best of automotive,” he adds.

Data has been collected from independent third-party comparison assessments of a pre-production twin CXO300 installation and a comparable gas installation. At cruise speeds between 40-46mph the CXO300 performed fuel burns of between 20-28gph, compared to the twin gas 300hp on the same boat, which produced a fuel burn of 24-35gph, at the same cruise speeds.

During the demonstrations, the engines were consistently reported to have low vibration, operational noise so low that regular conversation near the engine at cruise and full throttle was easy, impressive torque, good responsiveness and no smoke. Delivering 300hp at the propeller, the twin turbo V8-cylinder CXO300 employs four-stroke technology. The production engines will weigh 385kg, comparable to a 350hp gas engine, with three leg lengths available.

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