Patent ID: 8128442

Claim:
An outboard motor comprising: an engine including a crank shaft extending in an up-down direction; a drive shaft extending downward from the crank shaft and including a torsion bar spring; a propeller shaft; a propeller provided on the propeller shaft; a forward/backward switching mechanism arranged to connect the drive shaft and the propeller shaft with each other; and a vibration damper including a first cylindrical body and a second cylindrical body which are penetrated by the torsion bar spring; wherein the first cylindrical body and the second cylindrical body are coaxial with each other and overlap at least partially with each other, either of the first cylindrical body and the second cylindrical body having an upper end portion connected with an upper end portion of the torsion bar spring, the other of the first cylindrical body and the second cylindrical body having a lower end portion connected with a lower end portion of the torsion bar spring; a viscous fluid fills a space between the first cylindrical body and the second cylindrical body; at least one of the first cylindrical body and the second cylindrical body includes an inner cylinder and an outer cylinder, and the other of the first cylindrical body and the second cylindrical body is inserted between the inner cylinder and the outer cylinder; and the viscous fluid fills a space between the inner cylinder of the at least one of the first cylindrical body and the second cylindrical body and the other of the first cylindrical body and the second cylindrical body, and a space between the outer cylinder of the at least one of the first cylindrical body and the second cylindrical body and the other of the first cylindrical body and the second cylindrical body.