A floating marine vessel, an azimuthing thruster assembly, and an underwater mountable azimuthing thruster, having a movable and removable canister and a double mechanical seal and bearings enabling atmospheric pressure lubricating fluid to lubricate the thruster and seal assembly. The moveable and removable canister support the azimuthing thrusters with a propeller shaft axis oriented downwards at an angle 95 degrees to 110 degrees from a rotatable thruster input shaft axis, for reducing thrusts losses due to friction between the propeller wash and the bottom hull of the vessel and reduces thruster to thruster interference when multiple thrusters are operating on the same vessel.