Yanmar 6HYM-WET powered vessel will help investigate sustainable fishery options for Mauritius

Experienced Australian boat builder Steber International has powered its largest hull to date with Yanmar. Built for the Mauritius government, the Westcoaster-based hull will investigate sustainable fishing in the Indian Ocean.

The Steber International “Investigator Ⅱ”, at 60 ft is the largest and most ambitious project undertaken by the Taree-based boat builder to date

If you want to run a single engine in a vessel with a range in excess of 1,000 nautical miles off a place like Mauritius in the Indian Ocean, you had best have some serious confidence in that machine.

That is exactly the trust seasoned Australian boat builders Steber International and the Mauritius government had in the Yanmar 6HYM-WET (H-rating 500 mhp), the preferred choice for powering a new fisheries research vessel Investigator II.

“32 years ago we built our first boat for the Mauritius government,” Steber International’s Alan Steber explains with some obvious pride, “It was a 41 ft fishing vessel”.

A couple of years later the government bought a 47 ft fishing vessel from Steber Craft as a training vessel.

Both of those boats have had no hull or structure failures over all those years and still utilise their original steering and running systems, a credit to the quality Steber Craft have become renowned for.

Alan’s latest build for Mauritius represents a new milestone for the Taree-based boat builder though, launching their biggest boat to date and utilising a Westcoaster hull design.

Equipment and layout configured to maximise the boats purpose as a fisheries training and research vessel

At 60 feet, the hull is an original Westcoaster design, with the mould and intellectual rights purchased by Steber recently and upgraded to the new AMSA code.

Investigator II is a fisheries training and research vessel and has been purpose built with those activities in mind in terms of layout and deck gear.

It has a basic laboratory on board, including fume extraction tank for scientific dissection work on fish samples.

The vessel includes an eight cubic metre fish room which is designed and insulated as a manually-iced cool room. A transom crane system is designed to launch and retrieve anchoring systems for surface and seabed fishing and can also deliver FADs (fish aggregating devices) as part of the research work expected for Investigator II.

Three hydraulic (Australian made) fishing reels complement the deck gear onboard, capable of dropping up to three kilometres of line to the bottom. There is a clutched PTO off the main engine’s ZF325-1 transmission (assisted by a 200 litre hydraulic oil reservoir), that is coupled to all the hauling systems onboard, including a drumline capable of deploying longlining and pot capture equipment.

Fish room, drumline and reels comprised in the deck layout of the turnkey purpose built vessel

The boat includes a saloon that can seat up to 12 people in relative comfort with a large open-plan galley adjoining this area. This structure on the vessel, being larger than would be traditionally seen on a Westcoaster fishing boat, can also double as a training area for small groups onboard as required.

There are five accommodation cabins to sleep 12 also.

Saloon that can seat up to 12 people that also functions as a casual training room if required

With around 8 months in design and equipment decisions for the final configuration of Investigator II, overall it was simplicity that ruled in the final design.

“We had to keep the vessel simple to meet the needs of its deployment – no digital panels for operating systems where possible and simple labels on switches, valves and other equipment,” Alan explains, “This was one of the philosophies behind powering her with a single Yanmar too – a relatively simple, large displacement, reliable and easy to service engine.”

The 6HYM-WET is a purpose built marine engine which has delivered outstanding results for commercial boat operators worldwide.

The engine is a 6 cylinder in-line twin turbocharged configuration with single exhaust outlet and a displacement of 13.733 litres and an all up dry weight of 1,385 kgs.

The 6HY series is available with 4 commercial rated power outputs ranging from 500 mhp (368 kW) to 700 mhp (515 kW). For Investigator II the choice was made to use the conservative and heavy-duty continuous rating of 500 mhp (368 kW) @ 1950 rpm which powered her to 13.7 knots during trials– not a bad haul for a single 500 horsepower engine on close to 30 tonnes of vessel.

This model includes Yanmar’s latest combustion chamber design, named ASSIGN, a system originally pioneered by Yanmar on their large bore, low speed propulsion engines. The ASSIGN technology combined with Yanmar’s mechanical fuel system provides commercial operators with excellent fuel economy together with IMO Tier 2 emission compliance.

With close to 8,500 litres of fuel onboard across four tanks, there is an expected 1,000-plus nautical mile range.

A 500 hour service interval and sillicard-treated cylinder liners with nitrided stainless steel rings make for what Alan believes would be a “lifetime engine” for this boat.

“They are a good reliable engine and the client was keen to have the Yanmar because of their serviceability, support and reputation,” Alan said.

“It was also the client’s choice to have a single-engined vessel, and frankly, one good, reliable engine will last a lifetime”.

Yanmar 6HYM-WET 6 cylinder, in-line, twin turbocharged 500 mhp power plant

A Mase Mariner 1600 generator, (also distributed through the Power Equipment stable), provides AC power and utilises the four cylinder Yanmar 4TNV88 diesel engine to deliver its 15.3 kW of electricity. It delivers this power running at a frugal 1,500 rpm, making for a quieter engine.

This 2.1 litre power plant is not just a convenient source of reliable electricity, with easy-access to its sea water pump, air, fuel and oil filter positioning. The Mariner also incorporates automatic safety stops for low oil pressure or high water/exhaust temperatures to protect itself.

Even in its soundproofed cabinet configuration, the Mariner allows easy access for inspections and servicing, making it an ideal choice for the Mauritius government’s working crew needs.

Mase Mariner 1600 powered by Yanmar provides AC power throughout the vessel

Alan has visited Mauritius and the crews and skippers who have operated his vessels a number of times over the years, building a rapport with them.

Meeting a skipper who had been driving his boats since the first 41 footer more than 30 years ago was a real thrill according to Alan – that skipper thanking Alan for the quality of his boats and telling him “we have been out in some terrible seas at times and your boats have never failed us!”

“It was an honour to meet a man who had relied on us for so long,” Alan said.

The primary purpose of Investigator II will be to travel to remote areas and islands to fully investigate fisheries and the sustainability of fisheries in those waters. There is a species of shrimp in waters off Mauritius for example that hits the 18-inch mark and this will be among the fish and crustaceans studied as part of Investigator II’s work.

Alan and Steber International are thorough in their operational training for their vessels and set a benchmark in vessel operating manuals some 30 years ago. Such is the philosophy Alan sees in the Yanmar product too – clear, simple instructions to keep a reliable engine doing what it needs to do for thousands of hours.

“On launching the boat and during initial test runs there was no vibration, it is absolutely smooth and extremely quiet,” Alan added.

“The Yanmar is perfect all round from what we have seen in its initial runs.”

The fishing equipment (right down to terminal tackle) was part of the contract, a unique proposition for an exported Australian vessel.

Investigator II was run to Sydney from Taree, the 6HYM-WET serviced and oil changed with final checks, then cradle-shipped to Mauritius as a turnkey vessel ready for work.

Another fantastic partnership of quality Australian boat building and proven Yanmar and Power Equipment reliability to the world.

Simple yet effective instrumentation within the fully enclosed flybridge

Yanmars for 20 years in new Steber Craft

Steber International first started fitting Yanmars to its vessels nearly 20 years ago.

Since then, more than 140 engines have been used in new Steber builds, not including generators and ancillary power units such as fire pumps. Refits performed by the New South Wales mid-coast boat builder have also seen Yanmar repowering – with unbeatable reliability.

“Every Yanmar engine from day one has a strict commissioning process which guarantees everything is done to specification,” Alan Steber said.

“Being that most of our boats are built to survey, there is also no compromising on gearbox or shaft sizing which is no doubt a factor too.”

“Things like turbo-boost and back pressures, correct revs per engine – these are always right via the Yanmar and Power Equipment processes and of course our own insistence to ensure we are handing over a boat to clients that meets all required specifications.”

Another successfully completed build for Steber International. The “Investigator II” being loaded for it’s final journey to it’s home, Port Louis in Mauritius.