A new Grainger Raku 48 sailing catamaran on Queensland’s Sunshine Coast is not only sitting pretty with its stylish, high-performance design, but its Yanmars and Gori propellers have saved the day during her ocean adventures.
The Yanmar promise of unbeatable reliability and purpose-built marine diesel application has proven its worth and “saved the day” more than once for a Queensland-based recreational sailing couple on their new catamaran SV Mint.
With Yanmar long considered the blue-ribbon choice for sailing vessel auxiliary power, it is no surprise that Grainger Raku 48 owners Troy and Annette chose the combination of Yanmar 4JH5E (54mhp@3000rpm) engines and SD60 saildrives, coupled with innovative three-bladed Gori overdrive folding propellers.
Built on the Sunshine Coast, Troy was closely involved in construction and fitout from start to finish.
The Grainger Raku range are foam/glass composite in construction with epoxy glass skins and carbon reinforcement in selected areas. The Raku 48 is a true high-performance cruising platform with its 14.6 metre LOA being pushed by over 83 square metres of mainsail, 36 metres of jib and over 165 square metres of gennaker on a 20 metre mast. Mint tips the scales at around 8.5 tonnes lightships, but closer to 10.5 tonnes fully geared and provisioned for cruising.
While the designer recommends around 40hp engines for the Raku 48, Troy was keen to have a bit more performance available under power and opted for 4JH5E (54mhp@3000rpm) Yanmars.
“Putting the 54 horsepower Yanmars & Gori Propellers in was the best thing I did – we get eight knots under power at just over 2000rpm, and great economy especially when using the Gori Propeller overdrive function during motorsailing,” says Troy.
The Gori three-blade folding propellers chosen for Mint have an innovative overdrive function that can position the blades into a steeper pitch in forward via a simple technique of changing between reverse and neutral gears, without the use of vulnerable hydraulics or complicated mechanical devices.
The “overdrive” gives the same vessel speed at lower engine revolutions when motorsailing with the end result being less engine noise, less vibration and better fuel economy, factors much appreciated by Troy especially during long passages. The propeller in itself adds a new dimension to sailing under power. Qualities that are unique to the 3-blade Gori folding propeller.
Interestingly the Gori folding propeller can be applied to engines from 10 to 300 horsepower and the company has led the field in folding propellers now for more than 20 years – a nice synergy to the modern design and on-water efficiencies of the Grainger Raku.
Yanmar power and Saildrives that deliver in all conditions
A naturally aspirated engine, the 4JH5E Yanmar punches above its 2.19 litres engine displacement and nimble 201kg in weight.
Mint’s eight and nine knot performance under frugal revs are not only thanks to efficient hull design, but also the direct-injection efficiencies of the popular Yanmar diesel and output of the SD60 saildrive leg.
The 4JH5E delivers exactly what a sailing skipper needs – its highest torque (just under 160Nm) at low revs for easy dockside manoeuvrability but the majority of its rated power output at less than two-thirds of its maximum rated revs.
This gives the perfect combination of performance and fuel efficiency where they are needed most, making it a favourite of sailors worldwide. It also meets European RCD I, BSO II and EMC emission compliance along with US EPA Tier 2 emission compliance.
The SD60 saildrive is perhaps an unsung hero of Mint’s powerful performance under engines, with its simple and efficient design getting grunt to the propellers with vibration-free efficiency.
Among its proven features are a double seal mounting system between engine and hull (with water sensor for safety), clockwise or counter-clockwise configuration options and 2.23 or 2.49 ratio options.
The SD60 Saildrive can also easily handle power delivery up to an 80-horsepower engine yet only weighs in at 44 kilograms.
While the Grainger Raku range are lauded for their performance, they lack nothing in comfortable accommodations and fit out. Mint is no exception, with four comfortable queen-size berths, two bathrooms and a saloon and cockpit area that ooze modern luxury and materials with plenty of room.
Troy opted for electronic controls and dual stations (port and starboard) making for easy handling under power or sail.
The Raku design is not spartan in hull dimensions and engine mounting is slightly further forward than many catamarans. This gives reasonable engine room access (under the rear berths) that is helped by Yanmar’s compact design and the 460mm engine mount width of the 4JH5E engines. At just 560mm in engine width, daily checks and maintenance on these motors is easily accessed in even the skinniest of hulls.
The compact design of the 4JH5E at just 560mm in width and 871mm in length make an ideal solution for any catamaran allowing for easy access within the skinniest of hulls for daily maintenance checks. (Photo credit owners of SV Mint)
Yanmars to the rescue a long way from home!
With more than 500 hours already on Mint’s Yanmars, good performance under power and the beautiful fitout of their Grainger are not the only things Troy and Annette are grateful for.
A trip to New Caledonia in 2019 saw Mint’s Yanmars put to work in more ways than one, and literally saved the trip.
“Our generator actually failed early into the trip to New Caledonia and unfortunately it took many weeks for parts to arrive for a repair,” explained Troy.
“In the meantime we had to rely on running the Yanmars to keep our house batteries alive when solar charging couldn’t keep up – they really saved the trip.”
The 4JH5E utilises a 125amp (@12 volts) alternator as standard and was capable of keeping Mint’s lithium house battery system healthy for a number of weeks through the vessel’s charging and electrical management system.
“We also put a lot of hours on the Yanmars on the New Caledonia trip relying on getting places under power – particularly when we did a 200 nautical mile crossing to Vanuatu,” Troy said.
“That trip saw us run the Yanmars for around 20 hours all up because of a lack of wind,” he said, “and it is certainly nice to have a good motoring option when you’re trying to get somewhere!”
The Yanmars also saved the day again on Mint’s return journey from New Caledonia to Australia when a mainsail rigging breakage occurred early in the evening on a stiff 20-knot breeze.
“I didn’t want to be trying to fix rigging in those conditions in the dark, so we just fired up the Yanmars and motored for the night,” Troy said.
“It kept us on track safely and we didn’t need to worry.”
With the 4JH5E Yanmars sipping under four litres per hour each (under eight litres per hour combined) there was no stress involved with running engines for longer periods off Mint’s twin 270 litre fuel tanks.
Mint has her ropes thrown almost weekly from her home base with social sailing and racing or weekend runs to nearby islands. However, Troy and Annette have their eye on a Louisiades Archipelago rally later this year and like the idea of popping up the Queensland coast to the Hamilton Island Race Week also.
Racing under sails is in the couple’s blood, having run NACRA catamarans together in the 1990s. While things aboard Mint might not be quite as wet and wild as that kind of catamaran action, she is certainly a joy on the water with the performance of Yanmar/Gori propulsion.