When punching through the surf and heading offshore to your local fishing grounds, the more power and less weight you have, the better. Well, Yamaha’s 223 kW V6 F300 – the big daddy of their new range of four-stroke offshore outboards (including the F225 and F250) – delivers just that. It’s a whopping 112 kg lighter than the V8 F300 it replaces, and 23 kg lighter than the previous-generation V6 F250. The benefit: better boat performance and fuel economy. This 4,2-litre powerplant employs new materials and processes to make it lighter, more efficient and more powerful. Plasma fused sleeveless cylinders are used instead of steel sleeves to provide a durable surface for the piston rings. This not only reduces the overall powerhead weight, but also takes up less space in the engine block – which means there’s more room for the pistons. This process has allowed the boffins at Yamaha to gain the greatest displacement from the least amount of mass in the engine block, which also reduces overall weight. At the same time, it yields a surface that’s 60 per cent harder than a steel liner’s, for greater durability. An extra benefit is better heat transfer between the cylinder walls and the cooling system, improving cooling efficiency.
Another weight-saving measure is the lightweight composite engine pan. Made of sheet-moulded compound (SMC), it is 61 per cent lighter than its aluminium equivalent and provides greater protection against corrosion.
This motor not only has a greater displacement, but it breathes better than its predecessor, too. Its throttle valve is 13 per cent larger than that of the previous 3,3-litre four-stroke. Inside the engine you’ll find larger intake and exhaust valves and variable camshaft timing. The powerhead uses longer intake tracks and Yamaha’s exclusive In Bank Exhaust system to reduce back pressure and improve performance.
The end result: class-leading acceleration and top-end speed. Yamaha also claim it to be up to 13 per cent faster at cruise revs than other four-stroke outboards in the same power bracket. As cruise revs is where most offshore outboards are typically operated, this means you get there faster, using less fuel.
Powerhead innovations also improve fuel efficiency. The micro-textured cylinder walls (a result of the plasma coating process) create less friction and allow the pistons to move more freely, reducing parasitic losses.
Alternator output has been increased to 70 amps compared with the previous model’s 45 amps. The benefit is quicker-charging batteries. With more and more electrical equipment fitted on boats these days, that adds up to greater peace of mind and convenience for skippers.
It also features a new shift dampener propeller hub system to reduce the “clunk” that sometimes occurs on larger outboards when shifted into gear. It is compatible with the new Command Link Plus system that uses a single 13-cm highcontrast colour LCD screen to display engine, boat and other functions.
For added security, this outboard is also available with Yamaha Customer Outboard Protection (YCOP). This new, exclusive electronic system operates through the engine’s electronic control module (ECM), rendering it unable to start without the electronic key fob.
Expect to pay about R273 500 or about R281 700 for the counter-rotation version. For more information, visit www.yamaha.co.za