Valvet Oy Tern 25 hk Marine Engine The Valvet Oy Tern 25 hk is a robust, single-cylinder, gasoline-powered inboard marine engine engineered for reliable propulsion in small to medium-sized vessels. Delivering 25 horsepower (18 kW) of crankshaft power, it exemplifies Finnish precision in marine engineering, combining compact design with dependable performance for demanding aquatic environments. Key technical specifications underscore its efficiency and durability. With a displacement of 970 cm³ and a dual overhead camshaft (DOHC) combustion chamber, the Tern 25 hk achieves a high compression ratio for optimal thermal efficiency and power delivery. Constructed from lightweight cast aluminum alloy, it resists corrosion in saltwater conditions while maintaining structural integrity. The engine operates within a versatile RPM range of 1,600–2,700, paired with a manual transmission (±1) that allows precise throttle control and over-oiling capability to minimize shaft and gearcase wear. Fuel consumption is optimized at approximately 7.2 liters per hour at full throttle, ensuring low emissions compliant with stringent marine environmental regulations. A manual start system guarantees ignition reliability, even in adverse weather. Tailored for marine applications, the Tern 25 hk prioritizes safety and sustainability—evident in its emblematic lifesaver motif, featuring red for alertness, green for eco-friendliness, and white for simplicity. This design philosophy translates to enhanced operational safety, reduced mechanical complexity for easier onboard maintenance, and prolonged lifespan in corrosive seawater. Performance characteristics include balanced torque for smooth acceleration and fuel-efficient cruising, making it adaptable to varying sea states without compromising stability. Ideal for tenders, fishing boats, and recreational crafts, the Tern 25 hk excels in scenarios demanding reliability and environmental compliance. Its straightforward single-cylinder architecture simplifies servicing at sea, while the eco-efficient profile lowers operational costs. In essence, the Tern 25 hk embodies a harmonious blend of power, safety, and innovation, safeguarding maritime adventures with unyielding dependability. (248 words)