Triple Mercury 350HP Verado: 2017 Review
I laughed out loud when I went to the Mercury webpage to check specs – the first heading I saw was: ‘Intelligence Meets Testosterone’ then: ‘Outrageous Power – Refined Experience’. Those few words summarise this entire boat and engine test.
The Mercury Verado 350hp is a supercharged 2598cc inline six-cylinder engine with electronic fuel injection and air-to-air intercooler. It features electonic boost pressure control, sequential multi-port EFI, a 70-amp/882W belt-driven alternator, SmartCraft Digital diagnostics and built-in electro-hydraulic power steering. They come in three colours, including the Warm Fusion White here.
The recommended rev range is 5800-6400rpm, and the level, height and propeller choice – 20in Revolution 4 stainless steel four-blade – seemed right. In bumpy conditions, with four crew and 600 litres of fuel aboard, we hit 6000rpm WOT and as they were quite new I’d expect a few hundred revs more once run in.
A cold-air intake system is designed to capture cool air from outside the cowl and deliver it directly to the supercharger, while a unique labyrinth design in the top cowl keeps the powerhead dry. The slimmer inline (rather than V) engine design suits multi-motor fit-ups like this, and is aided by the streamlined cowl, while at 303kg the 350 Verado is the lightest in class, beating the Yamaha F350 V8 by more than 60kg per engine.
The new Flo-Torq Soft Shift Rubber (SSR) HD propeller hub system was noticeable, reducing the usual chunky gearshifts of the strong 5.44in-diameter Mercury Offshore gearcase with its 1.75 gear ratio and 1.25in prop shaft. Mercury claims it’s “the quietest and smoothest hub system ever created” and I can say it seemed to work. Soft gearshifts are enormously important when combined with joystick control, but in the case of this Boston Whaler without the joystick option, the old Mercury gear clunk wasn’t evident even in tight marina operations.
We got the frankly amazing Boston Whaler 350 Outrage hull planing by 3000rpm and 15.5kt. Open it up a touch to 4000rpm – easy with the light and user-friendly Digital Throttle Shift electronic binnacle – and we were comfortable at 29kt. What surprised me was the low total fuel consumption of only 118 litres per hour, giving us our best economy of 0.24 nautical miles per litre (0.44km/l). With an estimated on-water weight of almost 7000kg, plus our crew of four that’s an amazing result.
What amazed me more, though, was how the combination felt with more speed. Right up to our wide-open throttle maximum speed of 48kt, the triple 350s remained smooth and near-silent, and again weren’t bad on fuel with a combined flow of 348L/h. To put that into perspective, that’s each 350hp engine using 116L/h – a great result for so much oomph. It mightn’t be sensible, but by God it was fun!
SEA TRIALS:
Four people and 600L fuel on board, using single-lever control. Range calculated on 1514L fuel tank leaving 10 per cent in reserve.
| REVS | SPEED (KTS) | Fuel Burn L/Hr | Economy (Nm/L) | Range (NM) |
| 650 | 3.8 | 7.7 | 0.49 | 672 |
| 1000 | 5.3 | 13.7 | 0.41 | 527 |
| 1500 | 8 | 23 | 0.35 | 474 |
| 2000 | 9 | 35.4 | 0.25 | 347 |
| 2500 | 10 | 60.3 | 0.18 | 226 |
| 3000 | 15.5 | 84.7 | 0.19 | 242 (Planing) |
| 3500 | 20 | 98 | 0.21 | 278 |
| 4000 | 29 | 118 | 0.24 | 335 (Best Cruise) |
| 4500 | 33 | 163 | 0.21 | 276 |
| 5000 | 37 | 224 | 0.17 | 225 |
| 5500 | 42 | 352 | 0.12 | 163 |
| 6000/WOT | 48 | 348 | 0.13 | 188 |
ENGINES
MAKE/MODEL Triple Mercury 350hp Verado’s
TYPE Inline supercharged six-cylinder with EFI and intercooler
RATED 350hp
DISPLACEMENT 2598cc
WEIGHT 303kg
GEAR RATIO 1.75:1
PROPELLER Mercury 20in Revolution 4 stainless steel four-blade
SUPPLIED BY
Queensland Marine Centre
Unit 10, 71 Shipper Drive, Coomera, Qld 4209
PHONE +61 (7) 5591 7032
WEB sales@qmc.com.au
See the full version of this review in Trade-A-Boat #490, May 2017. Why not subscribe today?