A front support includes a second boss portion which extends toward a chain drive mechanism and to which a stator shaft is fixed. The second boss portion is inserted into a tubular portion of an impeller hub through a drive sprocket. An oil passage that communicates with a fluid transmission chamber is defined between the inner peripheral surface of the tubular portion and the outer peripheral surface of the stator shaft. A seal member that restricts an inflow of working oil from the oil passage is interposed between the tubular portion and the second boss portion. A shaft-side oil groove and a recessed portion which communicate with an in-case oil passage formed in the front support and the oil passage are formed between the second boss portion and the stator shaft.