Mercury Verado 400R outboard motor

Mercury Verado 400R Outboard: Motor Review

My copious flab and bulk – so handy for testing the stability of smaller boats – were not endangered the day I reviewed the Mercury Verado 400R outboard motor on a Force Crossover 26.

Mercury 400R Verado

Mercury Marine has scored with its Verado 400R. This masterpiece of marine engineering has no peers, yet for all its grunt it weighs 15 per cent less than its closest four-stroke competition, which develops only 350hp but needs a 5.3-litre V8 with quad camshafts to do so.

Even more amazing, the Mercury 400R power head has the same displacement as the Verado 200, which produces maximum power at 6100rpm, but doubles the output while revving only 600rpm higher. For all this power and torque, the WOT rpm range is only 6400 to 7000. Apart from different fuel mapping for the sequential multipoint EFI engine, the massive output increase is achieved by fitting a water-cooled supercharger, a radiator-style oil cooler and air intake vents around the power head top to supply more air to help dissipate heat. With power steering it’s 309kg – only seven per cent up on the 200.

Unusually for a four-stroke outboard motor, the maximum fuel efficiency zone is 4500 to 5500rpm, which really suits performance hulls. The engine has full OEDA three-star exhaust emissions compliance, achieved through excellent low rpm to midrange fuel efficiency. When trolling, the small displacement power head uses way less fuel than the big displacement competition.

The Cosworth-inspired 2598cc 400R engine is square – bore and stroke dimensions are 82mm, reducing piston speeds compared to the automotive-based competition. The double overhead camshafts are chain driven and roller cam followers eliminate the need to check clearance for the 24 valves. From observing production stages at the Fond du Lac factory in Wisconsin last year, the L6 engine as it’s known is built like a brick outhouse with plenty of meat between the four valves per cylinder and sparkplugs for a long service life. The engine also has provision for oversized pistons and rings should it require a cylinder re-bore and hone.

In addition to the DTS or drive-by-wire throttle and gearshift control, the standard power steering is light years ahead of traditional hydraulic steering. It’s precise yet light enough for any weakling to operate.

In my opinion the Mercury Verado 400R has revolutionised four stroke outboard engines.

400R Verado on the water

The engine was mounted so that its anti-ventilation plate was level with the bottom of the stepped transom but above the underfloor ballast tank outlet, reducing lower unit drag when planing.

The well run-in engine started instantly hot or cold and settled down to an almost vibration-free 600rpm in or out of gear, with no clunk when engaging gear, thanks to the standard drive-by-wire Digital Throttle and Shift system.

Unlike a 250hp outboard I tested, which returned its best planing fuel efficiency at 4000rpm, the Mercury Verado 400R was most efficient at 5000rpm – very unusual for a large four-stroke outboard. At 4000rpm, the 400R Verado used 28 per cent of the WOT consumption but efficiency (fuel used for distance travelled) wasn’t as good as at 5000rpm. There, the fuel flow was 39 per cent WOT but boat speed was almost twice as fast. In comparison, the 250’s fuel flow at 4000rpm was 29 per cent of WOT but by 5000rpm fuel was 49 per cent of WOT consumption for only a 32 per cent gain in boat speed.

Yet with a troll-to-plane time of eight seconds and another 23sec to WOT the 400R still has excellent midrange torque despite pushing a calculated total of 2.3 tonnes on the test day. Chosen by Force Boats, the 19-inch pitch Quicksilver Tempest three-blade stainless steel prop was a perfect match for the 26.

Mercury Verado 400R specifications

Mercury Verado 400R price: $39,810 RRP

With XL with Vessel View kit

Type Supercharged EFI four-stroke six-cylinder racing outboard motor

Rated BHP/MHP* 399.5/405.2 at 6700rpm

Rec. WOT range 6400 to 7000rpm

Piston displacement 2598cc

Bore x stroke 82 x 82mm

Gear ratio 1.75:1

Weights (dry) 309kg XL

                         315kg XXL

OEDA stars 3

* Brake horsepower/metric horsepower or PS