Yanmar 6LY440 Inboard Marine Propulsion Engine

Description

Reaching 440 BHP at 3,300 RPM from a 5.813L displacement block, the Yanmar 6LY440 Inboard Propulsion Engine yields high power density for sportfishing convertibles. This inline-6 diesel maintains 370 BHP continuous output at 3,178 RPM. Denso common-rail direct fuel injection requires 2-micron filtration, and high thermal loads demand scheduled heat exchanger tube bundle cleanouts.

A parent bore high-strength cast iron block integrates reinforced webbings to handle severe combustion pressures. The single-piece 24-Valve cast iron cylinder head features crossflow porting driven by a single overhead camshaft. Electrical systems operate on an isolated 12V 2-pole return circuit featuring a 3.0 kW starter and a 12V 130A alternator. Dimensions span 56.9in long, 29.4in wide, and 30.7in high, weighing 1,426 lbs with gearbox. Oil pan capacity holds 5.28 US gal.

Key Features of Yanmar 6LY440

Offshore tournament skippers buy Yanmar 6LY440 inboard marine propulsion engines to power express sport-fishers and fast rescue craft. Marine shipyards choose this high-output inline package for commercial workboat diesel engine repower installations in patrol boats.

• Denso high-pressure common-rail fuel injection operates with precision mapping to suppress exhaust smoke
• Turbochargers with wastegate control and seawater-cooled intercoolers deliver high torque across mid-range cruise bands
• Tubular freshwater heat exchangers protect internal cast iron water passages from corrosive ocean brine
• High-output 12V 130A marine alternators maintain battery reserves for commercial navigation electronics
• CAN-bus VC10 and VC20 vessel control systems transmit throttle commands without mechanical cable drag
• SAE 3 flywheel housings mate directly to ZF 280-1A, ZF 85A, or Twin Disc MG-5061A gearboxes
• Parent bore cast iron cylinders maintain thermal stability under continuous heavy ocean motoring duty

Bench Dynamometer Load Test Output

Dynamometer test records confirm 440 BHP peak output at 3,300 RPM and 370 BHP continuous output at 3,178 RPM. Turbo boost pressure stabilizes at 1.95 bar during continuous full-power runs. Freshwater cooling circuits hold engine block temperature steady at 182°F under sustained maximum power dyno pulls. Engine oil pressure maintains 55 PSI across operational engine speeds. Shaftline installation permits up to 15° static inclination angles. Crankshaft journal runout remains below 0.0004in TIR to protect bearings against deflection fatigue. Exhaust temperatures stay below 1,220°F during full power runs.

Field Operation Maintenance Service Rules

Electronic CAN-bus helm controls provide light lever action with under 2 lbs of hand resistance. Do not install this 3,300 RPM common-rail engine in heavy slow-speed displacement push-boats or vessels operating in shallow mud shallows without raw-water strainers. Operators must supply clean ultra-low sulfur fuel and maintain 2-micron fuel water separator filtration to protect high-pressure fuel pumps.

• Drain engine oil and change spin-on oil filter cartridges every 250 operating hours
• Inspect gear-driven raw water pump impellers and check zinc anodes every 250 hours
• Replace the primary 2-micron fuel water separator filter cartridge every 250 engine hours

Factory Warranty Shipment Parts Manifest

Yanmar Marine provides a 2-Year limited warranty backed by 3-Year major component structural coverage. The shipment crate contains the 6LY440 diesel engine core, ZF 280-1A marine gearbox, 12V 130A alternator, 3.0 kW starter motor, flexible vibration mounts, VC10 display panel, wiring harness, and factory technical manuals.