Couta Boat – Eva – GS858

The Couta boat is a class of sailing vessel that evolved in the southern part of Port Phillip, Victoria, during the late 19th century. These were originally working boats meant for fishing in the waters off the southern Victorian coast. Books have been written that describe the class in great detail so I won’t try to re-tell the story, a good summary and place to start for those interested can be found here.

Couta Boat, GS858 – Eva, is our own piece of Williamstown’s maritime history. Now over a century old, Eva was built by Frederick Blunt on a slip previously operated by the Blunt family where the Williamstown Police station stands today. Planking is New Zealand Kauri with the keel and stem of Western Australian Jarrah. The current decking which is not original is White Beech.

LOA 24′, 4″ (7.42M)
Beam 9′ (2.74M)
Freeboard 19″ (482MM)
Displacement 2.95 tons (3,000 Kg)
Ballast Weight Lead, 1.23 tons (1,250 Kg)
FWD (Fwd mastface Fwd Stem) 7′ (2.13M)
Sails WCB 1
Couta Boat Ass. No. C1910
Engine DC Electric 48 Volt Direct Stern Drive. 20 kWh LiFePO4 Battery Capacity
Historical Register: Australian National Maritime Museum – Register of Historic Vessels
Greg Blunt, the current owner of C. Blunt Boatbuilders, Nelson Place, Williamstown, explains the history of Eva and some of her colourful connections :-

“Frederick Blunt built her in 1910 for Old man Hegarty a pro fisherman who left it to his son Nugget Hegarty then to his kids who sold it to a chap at Mordialloc who Paul [Blunt, brother of Greg] bought it from under an assumed name to keep the price down then the two of us towed it back home where Paul did a full slow restoration. Old man Hegarty was found dead on our pier one morning, the pier was under repairs at the time, Joanne’s [Greg’s wife] father Bill fished with Nugget and reputedly took the Collingwood mob [Melbourne underworld gang from the 1920’s] out on fishing trips, on one trip I believe Squizzy Taylor went out with this mob , one always remained sober and packed heat, I have that from Nugget and Bill, Shackles can vouch for that also , Fred’s grave is in Williamstown cemetery”

After restoring Eva, Paul Blunt raced her on Port Phillip achieving considerable success.

Recorded Race Results
Classic Yacht Association of Australia – Cup Regatta – Couta Boats Division 2, 2008 – First Place. Paul Blunt, Doug Hem.
Beazley Working Boat Trophy. First Place 2007, 2008, 2009. Owner, Paul Blunt. Crew, Rob Pullen, Michael Hurrell. Skipper, Doug Hem.
Classic Cup Regatta 2008 – Second Place.
Classic Cup Regatta 2009 – First Place.

Diesel to Electric Conversion 2020 – 2021
In 2020 work got underway to replace Eva’s ageing Volvo diesel engine. After considerable investigations the decision was made to convert from diesel to electric auxiliary propulsion. The advantages are many, no noise, almost no maintenance and no smoke to name a few. A 10kW, 48 volt DC motor with digital control was selected for the task. This capacity delivers roughly the same shaft output as the Volvo 18 hp diesel as there are no significant losses to internal friction or heat. The electric motor has its own water cooling through a closed loop radiator which is a fraction of that needed for a diesel engine. The motor is connected to the prop shaft via three to one reduction gearing using a high performance, toothed industrial belt drive. A custom designed support structure secures the motor and drive shaft within the old engine bay, reusing the original timber engine mounts. Unlike traditional engine installations, propulsion forces are transferred to the hull through an independent thrust bearing structure. In this configuration, there is no propulsion load on the motor itself. The rotational forces of the motor shaft are transferred to the prop shaft using a jaw coupling. This device takes up any misalignment between the two shafts and has a rubber spider to absorb shock loadings.

Calculations were undertaken to size the right battery bank for the job based on the resistance of Eva’s hull through the water. To achieve 5 Knot cruising, the motor was predicted to draw 2kW of power with an efficient propeller fitted. Based on that power requirement, twin 10 kWh Lithium Ion batteries were selected to provide ten hours of cruising range. The range increasing or decreasing depending on the speed selected.

On water testing confirmed the calculated performance of the electric drive system and predicted cruising range. The batteries can be charged using shore power, wind, solar or petrol generator.

The experience on the water is remarkable, with almost no discernable noise coming from the motor itself. It is as close to sailing without sails as could be imagined.