Abstract: A method and a device for power transmission from a motor having a supercharging assembly, particularly a supercharged diesel-engine (7), to a gear (3) with a surface water driving propeller mechanism (4) mounted in a boat of the planing variety and preferably with a large propeller with a large pitch. A turbine coupling (10), which can be filled to a variable extent, is mounted between the supercharged motor (7) and the gear (3). The motor is designed to drive the pump portion (15) of the turbine coupling (10), and the turbine portion (17) of the turbine coupling (10) is connected to the input shaft (6) of the gear (3). The turbine coupling (10), when the boat is started, is emptied completely or partially, in such a way that it is at least partially disconnected from the gear. The motor is then accelerated to such a speed that the supercharging assembly of the motor (7) is connected.