Patent ID: 7896716

Claim:
A hydraulic saildrive apparatus comprising: an upper unit having an input shaft connected to an engine inside a boat; a lower unit having an output shaft including a propeller shaft, wherein a lower portion of the lower unit protrudes from a bottom of the boat; a first hydraulic pump driven by the input shaft, for supplying a working oil and a lubricating oil to the clutch from an oil reservoir; and a second hydraulic pump driven by the output shaft, for supplying at least lubricating oil to the clutch from an oil reservoir, wherein the upper unit is provided with a hydraulic forward and reverse switching clutch for transmitting the rotation direction of the input shaft to the propeller shaft, wherein the clutch is capable of changing the rotation direction between forward and reverse relative to the input shaft, and the output shaft is configured to rotate when the engine is driven and when the engine is stopped while the boat travels under sail.