A pair of OXE Diesel outboards on the latest Aus Ships build has delivered more than just a utility vessel that is a ‘jack of all trades’ – they have ensured Nereus will be king of the river in assisting and maintaining Brisbane’s ferry infrastructure.
OXE Diesels give work vessel versatile on-water ability and easy maintenance
Don’t be fooled by the functional looks and work boat practicalities of Aus Ships’ latest project Nereus, a 12 metre catamaran utility vessel.
Wearing two new OXE Diesel 200hp outboards, this is no slug of a work platform.
Designed primarily to deliver maintenance and fleet support for the terminals and ferries on the Brisbane River, the work vessel is yet another example of the versatility and game-changing abilities the OXE Diesel outboard platform is offering many boat builders and operators throughout Australia and New Zealand.
“As a support vessel, one of the main drivers towards going for outboards on the design was to keep maintenance low,” explained Aus Ships Director Tommy Ericson.
“The OXE Diesel outboards solve the fuel safety and consumption question and they still give an equivalent performance to the City Cats that operate on the river,” Tommy said.
The Nereus has been designed as a semi-displacement catamaran to deliver comfortable 17-20 knot cruise performance with minimal wake, (like the City Cat and Kitty Cat ferries on the Brisbane River) and is doing that speed for a fuel burn of around 50-60 litres per hour (combined) according to Aus Ships.
“I believe we were using a total of around 14 litres per hour at eight knots, so the range will be very good with the OXE Diesels if longer runs are necessary,” Tommy commented.
Having operated the Nereus for quite a few of its 20-plus hours of trials, Tommy is pleased with the vessel’s performance and handling.
“Compared to inboards, the noise and vibration is less – particularly at lower operating speeds,” he explained.
Excellent torque and control
“And the difference is significant in torque and thrust compared to petrol outboards.”
The fact that the OXE Diesel outboards on the Nereus are swinging 16X15 propellers is possible due to the stunning torque output of these 2.0litre, turbo intercooled common-rail diesel engines.
No less than 415nM at the engine in fact, converted to around 900nM at the propeller shaft via the OXE Diesel outboard’s unique belt drive system down the leg.
While the engine’s top rpm is 4,200, the torque peaks arrive at around the 2,000rpm mark,
“We believe it could spin even bigger props if they were available,” Tommy added.
The Oxe Diesel outboard employs what its manufacturers call Quick Shift Capability (QSC) and Low Speed Control (LSC). Its gearbox, (which is above the waterline at engine level – another factor in ease of maintenance), uses a twin multi-friction plate clutch which is electronically controlled. This allows the user to not only throw the outboard from forward straight into reverse with no risk of gearbox damage, but also delivers more positive control and shifting at lower manoeuvring speeds.
“You can comfortably ‘walk’ this vessel sideways,” says Tommy from his experience in trial skippering, “the engine torque, electro-hydraulic steering with power steering pump and the fact that the motors are four metres apart make it easy to position.”
Rivercity Ferries Maintenance Manager Shawn De Wit, who has recently taken delivery of the new utility catamaran, is quietly confident with what he sees of the OXE Diesel’s abilities so far.
“I have worked with Yanmar diesel outboards in a previous job years ago up in Papua New Guinea,” Shawn explained, “and I found diesel outboards to be good, reliable work horses.”
“The idea of the OXE Diesel outboards on this boat was floated by Aus Ships however.
“In terms of running outboards, they immediately solved the problems of the fuel cost and handling – we are all diesel in the fleet we work with so petrol outboards were a problem with fuel storage and cost.”
“We’re still in the trial phase of the vessel, but so far the (OXE Diesels) choice has been good – and fuel consumption seems to be great.”
Considering the OXE Diesel outboard uses a maximum of 45litres/hour at WOT according to its manufacturers, that’s not a surprising conclusion. Run a 200hp petrol outboard at full noise for an hour and you will see a significantly bigger number!
Shawn says the majority of tasks performed by the Nereus will revolve around ferry terminal maintenance and “ferry crew transfers, among other duties”.
“We work in a city where traffic is often congested, so the ability to move crews and equipment on the river makes things much more efficient.”
Aus Ships’ Tommy Ericson concurs with congestion-avoidance abilities of the Nereus, and says the vessel’s design gives the maintenance flexibility of “two blokes and a van” with an entire self-contained work platform (including high-power generator and a one-tonne, five metre reach crane) included.
“As a utility vessel it had to be able to do a number of things – movement of crews or VIPs, provide a work base for terminal maintenance and water/sullage transfers whilst also providing toilet and galley facilities for work crews onboard,” Tommy said.
“It is also in 2D survey (for 12 people) so it can service fleet vessels in the Moreton Bay islands if required in the future.”
Lower maintenance just beginning of OXE advantages
With an estimated 1,000 working hours for the OXE Diesel outboards each year on the Nereus, outboard maintenance will be a minimal interruption.
All service points for daily maintenance are readily accessed on the front of the engine, including raw water strainer and fuel/oil filters. The Aus Ships design has enabled easy access to the OXE Diesels’ cowls – a nice provision to an already easy-to-maintain engine.
The outboard’s scheduled service regime of 200 hours for routine services, (800 hours for extended services), mean this work boat can stay on the job for twice to four times the hours of an equivalent horsepower petrol outboard between services.
The OXE Diesel has high crash-stop robustness in the leg, made possible via the belt-drive system to the propeller shaft. With all major components on the OXE designed for modular replacement, downtime is reduced should major repairs ever be necessary.
OXE Diesel 125 – 200hp engines can also be configured to run either clockwise or counterclockwise propeller rotation, meaning the user is free to place the engine on any side of the stern, thus reducing the need for several spare engines to ensure redundancy.
Tommy Ericson said the OXE Diesel outboards also shine in alternator output too – and not just at peak output.
The OXE Diesel 200hp can deliver 130amps from its alternator, “but even at idle the engine is delivering around 50amps, which is more than enough to maintain electrical systems on the vessel – even to run the crane if the batteries require support – you can’t get that from equivalent horsepower petrol outboards,” says Tommy.
“And at the end of the day, the motors can be tilted up out of the water – it just makes everything easier all round in this application.”
What’s in a name – Nereus
In Greek religion, Nereus was a god of the sea said to have the gift of prophecy, great wisdom and the ability to change his shape. Among his other feats in mythology, Nereus is said to have assisted heroes in their endeavours.
Given the multi-task abilities of Aus Ships’ new build and her primary task of helping keep a ferry fleet running, there is perhaps no better title for this new OXE Diesels-driven vessel.
Discover what the OXE Diesel Outboard range can do on the water.