Big whammy for V8 Yammy

If six-cylinders simply aren't going to cut it for your outboard marine motor needs, Yamaha may have you covered with its stonking new V8 425 XTO outboard.

On sale in Australia from August 2018 and designed specifically to drive large props on bigger boats, the 425hp XTO or Extreme Offshore outboard has an all-new engine design that will "deliver extreme power and thrust," says Yamaha.

The XTO features a fully-integrated power and control system which, translated, means the thumping 5.6-litre naturally-aspirated V8 does away with hydraulic or electric pumps – an industry first claims Yamaha.

"Our engineering team have developed an industry-first fully integrated electric steering system, that has no mechanical hydraulics or electric pumps," said Jason Harris, Yamaha Motor Australia’s Marine Manager.

"This system is truly revolutionary, with industry leading features like rpm dependant lock to lock adjustment and steering friction adjustment at your fingertips."

With 'steer by wire' control and 'drive by wire' throttle systems, the beefy new Yamaha V8 425 XTO outboard gets an updated CL7 multifunction touchscreen display and an updated Helm Master joystick docking and positioning system.

The sleekly-packaged Yammy V8 outboard also features direction injection while improves fuel economy while ensuring "the highest compression ratio of any outboard" according to the Yamaha press statement.

A specially designed large diameter XTO OS propeller puts all that power into the soup, its large blades claimed to convey "extreme thrust". The 5.6-litre V8 outboard from Yamaha also gets reinforced internals inside an enlarged gearcase, with hardened gears and wide-span bracket and engine mounts tailored for offshore work.

The engine runs a big 90 Amp power generation system designed to run larger and more complex electric gizmos.

Maintenance matters have also been addressed; the Yamaha V8 425 XTO can be serviced while the boat is still on the water thanks to an in-water gear lubricant change-out system. A multi-faceted cowling allows easy access to several vital outboard elements too.

Specifications:
Engine Type: 4-Stroke, 32 Valve DOHC Direct Injection V8
Bore x Stroke: 96 x 96 (mm)
Displacement: 5559cc
Recommended Maximum RPM: 5000-6000
Fuel Management: EFI
Ignition: TCI
OEDA Emission Rating: 3
Lubrication System: Wet-sump
Alternator Output: 90 Amp high Output Alternator
Gear Ratio: 1.79 (25/14)
Starter System: Electric
Operation Method: Steer By Wire
Trim and Tilt Method: Power Trim & Tilt
Digital Gauges: Optional
Command Link Gauges: Optional
Transom Height (mm [inch])X: 640 [25.1] | U: 767 [30.1] | E: 894 [35.1]
Dry Weight (kg)X: 442 | U: 453 | E: 463