The V8 300hp FourStroke outboard is 33% quieter at cruise with 30% less transmitted vibration at idle than the leading four-stroke competitor.
FourStroke
FourStroke 250-300hp
Mercury 4.6L V8 250 and 300hp FourStroke outboards deliver legendary performance and an all-around elevated boating experience. Reliability. Comfort. Power. Handling. Easy ownership. Flexibility. For any body of water and across a wide variety of boats, every facet of a Mercury FourStroke outboard is engineered to ensure you make the most of your time on the water.
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FourStroke Performance Data
Exceptionally Smooth & Quiet
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- isolating mount designs, 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
Repower Your Boat with a New Outboard
It’s simple. When you repower your boat with a new Mercury outboard, you get to keep making memories in a boat you love, while enjoying the reliability, performance and efficiency that a new engine brings.
Warranty & Maintenance
Warranty Coverage
Mercury makes world-class marine products backed by world-class warranties.
Maintenance
At Mercury, we make maintenance easy. Learn more about how to keep your Mercury products performing at their peak.
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Resources
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Brochures
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Adventure Starts at Your Mercury Dealer
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