Mercury 400XXL 400HP – Verado Four Stroke 30-Inch Shaft

Mercury 400XXL 400HP Verado Supercharged

The Mercury 400XXL Verado is a high-performance 400HP outboard featuring the legendary supercharged Inline-6 architecture for the US offshore marine market. Utilizing a high-revving 2.6L 24-valve platform with charge air cooling and weighing 702 lbs, this engine is engineered for strong acceleration and a 7000 RPM ceiling. This 30-inch ultra-long shaft model is the premier choice for offshore high-transom vessels and large multi-engine offshore platforms. Our dependable outboard propulsion systems is designed to support the mechanical intensity and digital precision required for rigorous coastal operations.

Operational peak performance for the L6 Verado occurs between 6400 and 7000 RPM, utilizing a water-cooled supercharger to maintain consistent intake density and power delivery. The 1.75:1 gear ratio translates the supercharged boost into instantaneous hole-shot acceleration on large hulls. Manufactured in the USA, this corrosion-resistant marine engine incorporates SmartCraft Digital Throttle & Shift (DTS) and electro-hydraulic power steering to helps support a hyper-responsive, cable-free experience across turbulent offshore swells.

Technical Specifications of Mercury 400XXL Verado

Engine type Inline 6-Cylinder 24-Valve Supercharged

Displacement 2.6 Liters (158 cu in)

Horsepower 400hp @ 6400 RPM

Full-throttle rpm range 6400 – 7000 RPM

Fuel induction Sequential Multi-Port EFI / Supercharged w/ Charge Air Cooling

Alternator output 70 Amp (882 Watt)

Gear ratio 1.75:1

Shaft length 30 inch

Dry weight 318 kg (702 lbs)

Steering Electro-hydraulic Power Steering

Supercharged L6 Performance

The 2.6L L6 Verado is defined by its supercharged induction system, providing instant boost and torque across the entire power band. This technology helps support that American offshore anglers experience zero lag during acceleration, delivering the high-revving performance required to maintain speed in heavy following seas and choppy coastal inlets where naturally aspirated engines might struggle.

Ultra-Long 30-Inch Propulsion

The 30-inch ultra-long shaft is purposefully designed for offshore high-transom vessels requiring maximum propeller depth. This configuration prevents cavitation in large offshore swells and helps support consistent forward thrust on the heaviest deep-V hulls navigating unpredictable coastal waters, providing maximum hydrodynamic authority during long-range transits.

Charge Air Cooling Technology

To maintain peak thermal efficiency at 7000 RPM, the supercharger is paired with an advanced charge air cooler. This system reduces the temperature of compressed air before it enters the combustion chamber, preventing knock and ensuring that the 400HP output remains consistent during long-range offshore runs in high-temperature maritime environments.

Mercury 3-Year Protection

Every Mercury 400HP L6 Verado outboard is backed by a comprehensive 3-Year Limited Warranty for American owners. This factory-level protection helps support long-term peace of mind and grants access to genuine parts through a vast nationwide marine dealer network, reflecting a commitment to durability under high-stress conditions.

Maintenance & Longevity

Maintaining the 8.0L integrated wet sump lubrication system is vital for preserving the engine’s tight mechanical tolerances under supercharged loads. Always flush the cooling system with fresh water after every saltwater outing.Maintenance note: Follow the manufacturer’s service procedures and lubrication specifications for the engine and gearcase.