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Mercury Verado 400-hp outboard
Bigger! Stronger! Faster! Lighter!

Verado 400 on fishing boat

Mercury Verado 400 is suitable for center consoles, pontoon boats, bay boats and large sport boats.

Enter the dragon: Mercury Marine's 400-horsepower Verado outboard, the company’s highest horsepower Verado extant. One might reasonably ask: Do we really need this much power? Yes. As a matter of fact, we do. As boats get bigger and more capable, so too does the need for more horsepower. And for the record, way back in the 60s when Mercury introduced the world's first 100 horsepower outboard motor, some folks went absolutely ballistic. Wagging a finger, they warned that with that much power on the transom boats would go faster than 30 mph and people would be killed! That said, time marches on.

Suitable for center consoles, pontoons, bay boats, and larger sport boats

Today's Mercury 400hp Verado is suitable for center consoles, pontoons, bay boats, and larger sport boats. It should come as no big surprise to learn the power head is based on the 350 Verado's proven 2.6L inline-six that spins dual overhead camshafts that open and close 24 valves. You already know such a valve train improves performance all the way up and down rpm and maximized max power. Its supercharger boosts power and efficiency even further. Depending on installation and propeller pitch, the 400 Verado is designed for a max rpm of between 6,200 and 6,800.

The Verado 400 incarnation weighs 668 pounds. At first glance that might seem, a tad hefty. But taken in context, for an engine of this size, it’s almost a slim Jim. According to Mercury it qualifies as the lightest outboard in the 400+ horsepower category, boasting an enviable horsepower-to-weight ratio at 1.67 horsepower per pound. Want comparative numbers among the family of mega horsepower monster motors? See the chart below.


Monster motor lineup Weight
Seven Marine’s V-8 527 1,094 pounds
Suzuki Marine's V-6 DF350 727 pounds
Yamaha Marine V-8 425 XTO 952-pounds
Mercury Verado 400 I-6 668-pounds

Runs So quiet you can’t hear it idling

You should also know Mercury marine engineeers have been burning the proverbial midnight oil tweaking NVH (Noise, Vibration and Harshness). So how soft spoken is this potent outboard? According to a Mercury spokesman, at the helm station of a boat rigged with quad 400s, you can’t hear it idling. More particularly, poking along at 1000 rpm sound levels measure about 62 dB. Underway it's a bit louder at 78 dB, keeping in mind some of that noise is from the wind.

More good news, the helm's twin levers include digital throttle and shift capable of controlling an array of up to six outboards. Verado 400 is eminently compatible with Mercury JPO (Joystick Piloting for Outboards) and also works with Ray Marine's new DockSense technology for assisted joystick docking. Active Trim is available. A 70-watt alternator automatically senses load and increases idle rpm aas necessary boosting output in order to keep up with the demands of electronics.

Verado 400 is available in four colors: Phantom Black plus three shades of white. The idea being to lend color options to better match the boat's color scheme. The limited-warranty term runs for three-years

A final note, this engine is expected to fill the gap in Mercury’s lineup between its existing Verado 350 and Mercury Racing's 400R, which is designed more for speed and performance. In other words, the 400R is intended for racing than offshore recreational use.

Mercury Marine Verado 400 Specifications:
Block configuration Inline - 6
Displacement 2.6L
185 CID
Valve train OHC 24 valves
Air induction Supercharged w/charge air cooling & electronic boost pressure control
Fuel induction Sequential multi-port electronic fuel injection (EFI)
Full throttle RPM 6200-6800
Recommended Fuel 89-Octane gas
Alternator 70 Amps
Warranty term Three years