YANMAR 6LY400 Marine Diesel Engine 400hp

The new 6LY takes the all the attributes of its forerunners and adds major engineering advances. The beating heart of the engine remains the international powerboat racewinning compact 5.8 -litre in-line six-cylinder YANMAR engine block that over three decades has cemented its popularity with boat designers, builders and owners who laud its performance, fuel efficiency, reliability and smooth and quiet operation.

This latest incarnation has taken the engine into a new era of mechanical and digital sophistication. We have completely re-engineered the fuel induction and aspiration systems - all functions now being managed by state-of-the-art electronic precision for even better all-round performance. We’ve replaced single injectors with a high-pressure common-rail fuel system to deliver exceptionally finely atomised fuel to the cylinders for better power-to-weight performance, fuel economy and smooth running. 

There’s also a new 24-valve cylinder head which, with a redesigned inlet and exhaust manifold, optimises engine breathing. All this makes the 6LY one of the most efficient, refined and easy-to-live-with marine diesel engines in the 400-500 mhp power segment on the market today. It’s ideal not just for new-builds, but for refits too. Sharing the compact footprint of its predecessors, it fits perfectly into engine rooms housing earlier 6LY models and other similar engines. The 6LY400/440 connects easily with existing mechanical controls. Fingertip controllability For the ultimate in easy and precise boat control, YANMAR offers the latest VC10 ‘fly-by-wire’ vessel control system to give precision gear changing and throttle adjustment with perfect ‘feel’. And with the joystick control option as part of a fully-integrated YANMAR engine and controls package, docking is also really easy. Single- and YANMAR 6LY - the rebirth of a legend Our fourth-generation 6LY marine diesel series builds on the virtues of its classic six-cylinder forerunners, advancing efficiency and lowering emissions. dual-lever control heads have push-buttons for function selection. Operations are precisely monitored on 3.5-inch robust IP66-rated display screens with IP66 waterproof rating and with full diagnostic capabilities plus UV-protection, anti-dazzle coating and anti-fogging ventilation. For maximum operational security, two parallel CAN bus networks separate engine and monitoring functions. YANMAR’s J1939 control bus is dedicated to the engine and drive control system while GPS, chart plotter and monitoring displays are handled by NMEA2000 data bus so that, in the unlikely event of J1939 failure, the system automatically switches to a pull-out back-up panel. VC10 offers operation modes for single and twin-inboard or sterndrive installations. All are designed for easy serviceability and are readily expandable to allow owners to extend monitoring capability at any time.