June 18, 2008 It’s not that long ago that outboard motors had a lot less power than they have today – outboards have seen enormous progress in a short time, not just in power output, but also in the sophistication of their emission-reduction technologies. One prime example of this we found this week in the world famous Sydney Harbour, Australia, where the H2O taxis provide a massive water taxi service across 200 local pick-up and drop-off locations around Sydney Harbour from the Parramatta River to Manly and all the way through to Homebush Stadium. The company company upgraded its flagship 10.8m WaterBus fleet, from twin Yamaha F225 outboards to twin 5.3 litre V8 F350s. Not only did it comfortably increase cruising speeds, it also halved the fuel consumption required to push around a five tonne boat with as much as three tonnes of passengers and luggage.
The flagship 10.8m H2O ‘WaterBus’ now boasts 700hp to deliver its fully customised taxi services.
“I had already done over 3000 hours on my two Yamaha F225 4-strokes and was looking at upgrading to the F250 models when the new V8 F350 hit the market,” explained Shane.
“On a full load my twin F225 outboards were really working hard. Having the two Yamaha V8 outboards on the back has transformed the performance of this large, heavy boat.” H2O Taxis owner Shane Kearns
“Over the 35 engine hours clocked so far I have nearly halved my fuel bill with the twin F350 outboards returning a combined 31 litres per hour across a range of harbour conditions and boat loads. I originally thought my fuel gauges were wrong until I started closely monitoring my fuel intake.”
Shane Kearns bought the 10.8m aluminium tri-hull nearly 2 years ago, which was built to survey in 1995 for the renowned Doyles Restaurant and licensed to carry 26 passengers. After some customising and an engine swap from twin Yamaha 2-strokes to the F225 4-strokes, the vessel was re-surveyed to carry 49 passengers and the roof rated to 1 tonne for equipment transport to fulfil a range of water taxis duties.
“With the F350s on the back, I travel at an average speed of 18-22 knots with the engines sitting comfortably on 3000 rpm,” said Shane. “Changing the prop from 15” to 19” has produced incredible thrust with the boat wanting to push forwards at idle revs. I opened her up to 5,000rpm recently which produced 38 knots.” Yamaha’s world-first V8 F350 outboard has been warmly embraced by the Australian boating market with leading local and imported boat brands looking to the V8 for unmatched power to weight performance. Redefining the power options for larger planning vessels, the V8 F350 produces the torque expected from an inboard, with the weight, access and space saving advantages of an outboard. And skippers across Australia are savouring the advantage.
“Our WaterBus feels more balanced with the two V8s on the back and planes a lot easier than my previous setup,” said Shane.
“In the last 21 months I have done approximately 20,000 nautical miles (37,000 km) around the harbour and clocked up over 3000 hours on my original F225 4-strokes. I now have every reason to expect big things from my new Yamaha V8 outboards.”