Abstract: A walk-behind self-propelled device comprises a main frame including a base portion and a handle portion; a pair of wheels secured to the base portion for engaging the ground surface; an engine mounted on the base portion; a hydraulic pump carried by the base portion and operably connected to the engine; a first hydraulic motor directly coupled to the wheels and operably connected to the hydraulic pump; an attachment secured to the base portion; a second hydraulic motor directly coupled to the attachment and operably connected to the hydraulic pump; and first and second valves for controlling the first and second hydraulic motors, respectively. Each of the first and second valves has a bypass position whereby hydraulic fluid bypasses the first and second hydraulic motors. First and second handgrips are provided for operating the first and second valves, respectively.

Abstract: A detachable moldboard dozer blade assembly for tractors having a push frame pivotally attached at a rear end thereof to the underchassis of a tractor. A frame structure is attached to the forward end of the push and provides for a vertical pivotal axis for the attachment of the dozer blade assembly. An attachment plate is pivotally connected transversely to the frame structure for blade movement in a horizontal plane and shim and plate means retain the attachment of the dozer blade assembly. An attachment plate is pivotally connected transversely to the frame structure for blade movement in a horizontal plane and shim and plate means retain the attachment plate to the dozer blade to permit vertical or tilt movement of the dozer blade relative to the attachment plate. Hydraulic piston means extend from the push frame to the attachment plate and from the attachment plate to the dozer blade to move the dozer blade about a vertical and horizontal plane.