Main Engine 4-Stroke · Main Engines (4-Stroke)
Large marine vessels often require powerful and reliable engines to propel them across oceans. The Wärtsilä 9LW31SG engine is a dual-fuel unit designed to meet these demands. It boasts a robust 2700kW output, fueled by LNG (Spark-Ignited). With a 9-cylinder configuration, a bore of 310mm, and a stroke of 430mm, this engine delivers a mean effective pressure of 30 bar. The 9LW31SG operates at a speed of 750 rpm and features two-stage turbocharging with intercooling for enhanced performance. Its fuel injection system utilizes common rail direct injection for precise fuel delivery. Weighing approximately 57.1 tonnes, this engine incorporates a 4-stroke design with 2 inlet and 2 exhaust valves per cylinder. The 9LW31SG has a piston speed of 10.75 m/s and a specific fuel oil consumption of 167.7 g/kWh at its optimal point.
Do you have the manufacturer datasheet for this model? Send it with the enquiry form — we check it and name the source.
Free of charge — send us your request for Wärtsilä equipment. Our team checks it and replies by e-mail.
Other models of the same equipment type, Wärtsilä first.
Tell us what you need for this Wärtsilä 9LW31SG — a part, a service call, a second opinion. Are you Wärtsilä? Claim this brand page.
Service engineer? Write the day report for this 9LW31SG in OceanSphere Work — photos, hours and parts, as a PDF for the owner. Try it free for 14 days →
Yes. Specifications, documents and service notes for this model are readable without an account. An account adds saved searches and requests, nothing is taken away.
Yes. Tell us the manufacturer, the model and what you need — a person reads every request and replies by e-mail.
Send us the nameplate or the correct value. We check it against the manufacturer datasheet or class-society record and update the page.