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Seawork International: Cox Diesel Outboard Performance Wins Industry Seal of Approval

Press release   •   Jun 14, 2019 14:59 BST

The demonstrations took place throughout the three-day event at Seawork. (Photo credit: Adam Hollingworth)

British diesel outboard manufacturer, Cox Powertrain, chose Seawork as the platform for the first public demonstrations of its long-awaited 300hp diesel outboard, the CXO300. More than 120 people from the commercial workboat sector, including distributors, boat builders and end users took to the water to experience first hand the outstanding performance of one of the most talked about marine engine developments in recent years – and it didn’t disappoint.

The demonstrations took place throughout the three-day event in partnership with Cox Powertrain’s UK distributor, Berthon Power. Simon Barnett, Berthon’s Power’s UK and Ireland Sales Manager said, “There is a big demand for a high-power diesel outboard and commercial users recognise the huge benefits that such an engine will deliver. We were absolutely delighted with how the trials went and with the extremely positive feedback that we received from our customers.”

David LeBlanc, Cox Powertrain’s Louisiana based distributor, Innovative Diesel Technology, was impressed by the amount of hard work and innovation that has gone into developing the CXO300. After his demo, he said, “After thirty years in this industry, I can say with confidence there is nothing out there like this engine. From its clean burning, smooth running, durability and massive power, the engine will truly change the market.”

As a heavy-duty diesel-powered outboard engine, the CXO300 brings reduced maintenance and haul out costs to commercial workboat users, reducing disruption to the vessel’s operation. The CXO300 offers at least a 25% better range compared to a gasoline outboard and it has a 100% higher peak torque at the crankshaft than the leading gasoline 300hp outboards, enabling the craft to move more weight more efficiently, reach peak torque and top power more quickly.

Production of the CXO300 will commence this autumn at Cox Powertrain’s state-of-the art facility in Shoreham, West Sussex with the first engines scheduled for delivery in Q4 2019.

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Notes for Editors:


£35,000 GBP/€43,000 EUR/$50,000 USD/

Key technical specifications

Crankshaft power, kW (hp) 252 (338)
Propeller shaft power, kW (hp) 224 (300)
Engine propping speed, rpm 3700-4000
Displacement, L ( 4.4 (266)
Number of cylinders 8
Bore/stroke, mm (in.) 84 (3.3) / 98.5 (3.9)
Compression ratio 16
Ratio 1 (Propeller speed) 1.23:1 (3259)
Ratio 2 (Propeller speed) 1.46:1 (2739)
Peak torque, Nm (lb.ft) 650 (479)
Aspiration Twin-turbo
Shaft Length, inch(mm) 25” (635)/30” (762)/35” (889)
Emission compliance EPA 3, IMO 2, RCD 2
Start assist Glow plugs
Rating Light-duty commercial
Trim range -4° to +16°
Tilt range 71°
Engine oil spec API CI-4 / SAE 5W40
Gear oil spec API GL-5 / SAE 75W140
Propeller spline spec 1.25” shaft / 19 tooth
Colour options Black / White

Media contacts:

Faye Dooley, Marketing Communications Manager

Cox Powertrain Limited

Tel: +44 (0) 1273 454 424


Media information & images:

Karen Bartlett

Saltwater Stone

Tel: +44 (0) 1202 669 244


About Cox Powertrain

Cox Powertrain is a world-leading British design and engineering innovator of diesel engines developed for worldwide and multi-market applications.

Based on the South Coast of England, Cox Powertrain is backed by a solid shareholder base of private and institutional investors. As a result, the company has been able to implement a long-term development programme of ground-breaking new products.

Led by ex-Cosworth CEO, Tim Routsis, whose background lies in engine development in global automotive, aerospace and marine markets, the company’s mission is to deliver a completely new concept in diesel engines that has the potential to revolutionise the marine market.

With a strong pedigree in Formula 1 racing and premium automotive design, Cox’s highly skilled team of engineers has decades of experience in combustion engines and understand the many difficulties customers are challenged with.

Cox’s first ground-breaking diesel outboard performance engine, the CXO300, is the highest power density diesel outboard engine ever developed. As a high power, single fuel engine, the CXO300 delivers the same performance and efficiency of an inboard but with the convenience and flexibility of an outboard.

The CXO300 is due to go into full production in Q3 of 2019. Cox is supported by a worldwide distributor network made up of 40 distributors and 400 dealers.

For further information, visit