Selva Murena EFI 25XS 4-Stroke Outboard Engine Extra Long Shaft

At its heart, the Murena 25XS EFI uses a finely balanced 498 cc SOHC 16-valve engine tuned to provide maximum torque throughout the 5 000 to 6 000 rpm range. The EFI system continuously adjusts fuel delivery and ignition timing to suit load and environmental conditions, guaranteeing smooth acceleration, clean combustion and notably low emissions. Despite its small displacement, it delivers thrust comparable to larger motors thanks to an optimised combustion chamber and Selva’s precise calibration of valve timing. The broad torque band allows the engine to plane heavier hulls quickly and maintain speed with less throttle, translating directly into fuel savings and extended range.

The engine block and cylinder head are cast from corrosion-resistant aluminium alloy and mounted on a reinforced lower unit built to absorb continuous high load. A 13 : 24 gear ratio, paired with a large-diameter three-blade propeller, converts torque into smooth, efficient thrust with excellent grip in turns or current. Cooling is managed by a sealed, pump-forced system that keeps operating temperature stable even at prolonged idle. All major components receive Selva’s marine-grade anti-corrosion treatment for longevity in salt or fresh water. The Extra Long Shaft (XL) configuration provides deeper propeller immersion and better tracking for sailboats and deep-transom craft operating offshore.

Starting is effortless through the electric ignition supported by the EFI’s automatic enrichment control, ensuring instant firing in cold or humid conditions. The engine runs with remarkably low vibration thanks to Selva’s internal balancing and resilient mount design. Operators can equip Power Trim and Tilt for quick attitude adjustments and easier mooring or trailering. A 12 V / 200 W alternator provides stable power for electronics, navigation lights and bilge systems. Servicing is straightforward, with easily accessed oil, filter and inspection points that minimise downtime. Compact, economical and powerful for its size, the Selva Murena EFI 25XS 4-Stroke Outboard Engine (Extra Long Shaft) represents the ideal combination of torque, efficiency and long-term reliability, delivering confident control and enduring Selva quality on every voyage.