Yanmar, a diesel engine manufacturer since 1912, is throwing a spanner in the works with the announcement of an electric motor. And for this, the Japanese engineers have been very clever. Rather than completely reinventing the concept, they have adapted an electric motor to their Sail drive baseplate. So a sailboat - this motor is designed for sailboats - can simply be fitted with either a diesel or an electric motor on the same engine chassis.
Three powers
Today, the model is available in 3 power ratings: 7, 10 and 15 kW, equivalent in the diesel range to 10, 15 and 20 hp. Although they will differ in pitch and diameter, the propellers are standard models in the range, with 2 or 3 blades, fixed, folding or feathering.
The brushless electric motor operates on 48V. It is mounted directly on the Sail drive baseplate. It is delivered as a complete package with battery pack and charger. Available in 10, 20, 30 or 40 kW. The motor is cooled with the same oil as the baseplate. No water circulates around it. So installation doesn't even require a through-hull. In the absence of air ventilation, this motor is particularly quiet, and the manufacturer does not recommend soundproofing the engine hold. Maintenance is limited to anode and oil change. As simple as servicing a Sail drive baseplate.
Tested on Saffier SE33
We tested this model on Saffier SE33, an 11 m dayboat weighing 3 tons. Start-up is as simple as pressing the start button next to the engine control. The Yanmar display shows all the relevant information, including the remaining energy in the batteries and the charge level. A running time indicator, which varies according to speed, enables you to find the best compromise between speed and range. With the engine at full throttle, we reached 7 knots, which is more than enough for a sail-powered dayboat. At this speed, the noise you hear is that of the propeller in the water. The engine itself is quiet, with no annoying whistling.
The whole point of electric propulsion, in addition to the absence of pollution, lies in the torque provided by the engine. To make maneuvering easier, Yanmar has installed a solution that delivers higher revs (3300 rpm max vs. 2900 max in forward gear) when shifting into reverse. A sort of boost that compensates for the propeller's deficiency in this direction of rotation.
Accessories to prevent you from getting stuck
A second screen, installed in the cabin on our test boat, enables better management of the battery park. What's more, a manual control, protected by a watertight cap, replaces all controls in the event of a power failure. With this small control, you can move forward or backward and accelerate with a potentiometer. It's not very practical, but it'll get you out of a tight spot in the event of a problem. On our test Saffier, this control is installed in the rear trunk, not really accessible, but at least present.
Rates to be defined
Prices for these 3 engines and battery packages are not yet available.
