Marine drive having two counter-rotating surfacing propellers and dual propeller shaft assembly

摘要

A marine drive (10) has two counter-rotating surface operating propellers (12, 14). Inner and outer concentric counter-rotating propeller shafts (40, 42) are supported by a spool assembly (38) locked and retained against rotation and against axial movement in the lower horizontal bore (28) in the torpedo (34) of the drive housing (26) by axially spaced left and right hand threads (44 and 46). A thrust bearing assembly (98) transfers thrust from the outer propeller shaft to the inner propeller shaft during rotation of the propeller shafts in opposite axial direction and is axially located between fore and aft driven gears (76 and 78). Propeller shaft sealing and bearing structure, and propeller self-centering mounting structure is provided.