The Adaptive Speed Control feature lets you maintain engine rpm despite changes in load or conditions. Climbing large swells is easier. Cruising at low speeds is smoother. Carving out tight turns is effortless.
FourStroke 250 - 300hp
3.4L V6 and 4.6L V8
Reliability, flexibility, power and efficiency – all within your reach. Backed by decades of marine power innovation and product leadership, Mercury V8 and V6 FourStroke outboards deliver legendary performance and forward-thinking technology. FourStroke outboards are built for any body of water and a wide variety of boats.
Intuitive, Innovative Features
Adaptive Speed Control
Smooth and Quiet
Featuring a large muffler and a vibration-dampening cowl design, Mercury V8 FourStroke outboards deliver an exceptionally smooth, quiet ride at any speed.
Easy to Maintain
The exclusive Top Cowl Service Door simplifies routine maintenance, letting you check or add engine oil without removing the top cowl. An hour-based maintenance schedule decal is located under the cowl, providing a quick overview of routine maintenance.
Ample Charging Output
A powerful alternator delivers 85 amps of charging power at wide-open throttle – perfect for keeping onboard electronics running long into the fun.
Industry-Exclusive Battery Management Technology
When needed, the idle charge battery management system works for you by monitoring battery voltage and adjusting engine rpm at idle to boost alternator output.
FourStroke Performance Data
Exceptionally Smooth & Quiet
The V8 300hp FourStroke outboard is 33% quieter at cruise with 30% less transmitted vibration at idle than the leading four-stroke competitor.
High Displacement
The high-displacement, quad-cam design of the V8 FourStroke powerhead generates serious torque, especially at mid-range, for quick acceleration and exciting speeds.
Light & Compact
The V8 300hp FourStroke outboard is the lightest in the 300hp class by more than 20 pounds. Both V8 models mount on 26-inch centers for easy repowers or new installation on a wide range of boats.
FourStroke Advantage
Comfort
With a balanced powerhead and sophisticated, vibration-dampening cowl design, Mercury FourStroke outboards deliver an exceptionally smooth and quiet ride at any speed.
Durability
Premium corrosion-preventive technologies and durable components ensure FourStroke outboards can stand up to the most demanding marine environments.
Compact Design
Ideal for new engine setups or repowers, the slender width of a Mercury FourStroke outboard fits most transoms, including those with narrow engine wells and tight motor spacing.
Efficiency
Explore farther and stay out longer thanks to impressive power-to-weight ratios, intelligent fuel systems and optimized fuel injection (on most models) that maximize performance from every drop of fuel.
Engine Specifications by Horsepower
SmartCraft® The Power to Do More
SmartCraft® is a full suite of digital technologies, fully integrated and totally coordinated. Gauges, sensors, vessel systems, computer-controlled features – one total package, one high level of control. Make your boating experience easier, safer and a lot more enjoyable.
Time for New Power?
Replacing an old outboard can deliver improved performance and reliability, increased fuel economy and better handling for a more enjoyable boating experience. The entire family of FourStroke outboards is lightweight and compact, making those engines perfect for repowering older boats.
Warranty and Maintenance
Warranty Coverage
Mercury makes world-class marine products backed by world-class warranties. You can also add a Mercury Product Protection (MPP) extended service contract that covers certain expenses caused by defects in materials and workmanship after the Mercury Limited Warranty expires.
Maintenance
Mercury FourStroke outboards are thoughtfully designed to minimize maintenance and ensure you get the most joy from your time on the water.
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Learn More About FourStroke Outboards at a Mercury Dealer
No one understands marine performance like your local Mercury Authorized Dealer. Contact a dealer today to learn how you could power your adventures with a FourStroke outboard.