New Yanmar Powered Ferry Operating in the Whitsundays

The passenger ferry market continues to be a growing market segment for new boat projects and repowers alike, particularly for Yanmar’s range of commercial engines. 

The recent launch by the highly respected Queensland boat builders, Aluminium Marine, of their latest vessel, Cobia, represents another significant milestone for both Aluminium Marine and Yanmar. 

Having previously built four Yanmar Powered Incat Crowther designed vessels, such was their confidence in the performance and marketability of the 24 m design, Aluminium Marine took the bold step and commenced construction of this vessel as a stock build in 2012. Nearing the end of the build process, their decision was rewarded, and the boat was purchased by Cruise Whitsundays and ultimately named, Cobia. 

The power of choice for this vessel is a pair of Yanmar 6AY-WGT marine diesel engines. These are resiliently mounted close coupled to Yanmar’s own YXH-240 marine transmissions. These in turn, driving five blade (35’ x 36”) propellers which combine to deliver the design speed of 25 knots effortlessly. 

This new vessel has an overall length overall of 24m with a full 8.5m beam. Lightships, Cobia tips the scales at 58 tonnes, but fully laden with 200 passengers, including 5 crew, and full fuel/ water tanks, the boat displaces 80 tonnes. 

According to Jack Louwerse, Engineering Manager at Aluminium Marine, the decision to specify Yanmar for this build was easy. 

“We have used quite a number of Yanmar marine diesels in our other boats over the years, and our clients have not been disappointed yet,” said Jack Louwerse. 

“The robust design of the Yanmar engines and their simple non-electronic governor system are their key attributes for us, and our clients. These are purpose built marine engines, not converted truck motors. As such they are durable, easy to service and highly suited to the marine environment.” 

“When we build a ferry and ship it off to a distant location in Australia, or even overseas, we demand the best in reliability and durability for clients with all components installed, including the main engines.” 

The Yanmar 6AY Series engine provides a choice of flexible power outputs to cater to a range of uses, from high speed vessels such as the Cobia passenger ferry through to ROPAX and displacement hull workboats, such as fishing trawlers and tug boats.

The 20.379 litre, 4 valve in line 6 cylinder, turbocharged and intercooler diesel engine boasts four power ratings between 485kW ( 659mhp) @ 1900rpm to 671kw (911mhp) @ 1940rpm, depending on the application and duty cycle proposed. The Cobia is fitted with a pair of 6AY-WGT engines which are rated at 911 mhp (670 kW at 1938rpm). Engine weight (without the gearbox) is 2365 kilograms.

This model engine is highly rated with commercial customers reporting good acceleration, reliable performance and unmatched fuel economy.

The 6AY engines use a staggered injection nozzle and patented combustion chamber design named ASSIGN which was developed by Yanmar originally for their large bore, low speed propulsion engines. This technology has enabled IMO Tier 2 emission compliance with no electronic controls and a fuel consumption specification of between 220 and 208 g/kW-h at 100% load depending on the rating used.

The standard service intervals are 500 hours with all service points easy to access by the nature of the inline 6 cylinder design, cylinder block inspection ports, and the individual cylinder head design configuration. All factors especially favoured by operators of commercial catamarans, where engine room space is generally restricted. 

Power Equipment is the exclusive and authorised Australian, New Zealand, Papua New Guinea and South Pacific Distributor of Yanmar Marine and Industrial diesel engines, JCB DieselMax, MASE diesel marine generators, Gori high quality folding sailboat propellers, PSS Shaft Seals, Electromaax and Arctic Steel products.