Main Engine 4-Stroke · Main Engines (4-Stroke)
The Yanmar 8L6N21L diesel engine operates on a vertical single-acting inline configuration, featuring a 4-stroke cycle with direct injection and compress air motor starting. This design allows for efficient combustion and reliable operation in marine applications. The engine is equipped with a bore of 210 mm and a stroke of 310 mm, delivering a power output of 1680 kW at 750 rpm. It runs on Heavy Fuel Oil (HFO) or Marine Diesel Oil (MDO) and includes features such as a compression ratio of 16.8:1 and an oil consumption rate of less than 1.1 g/kWh. Common maintenance issues include turbocharger oil leakage, fuel injection system carbon deposits, seawater cooling system corrosion, crankshaft journal issues, and oil sludge accumulation. Regular inspections for these issues, including checking turbo seals, measuring boost pressure, inspecting fuel cleanliness, examining zinc anode wear, and conducting oil analysis, are recommended to ensure optimal performance and longevity.
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