A swiveling utility machine includes a swivel deck, an engine disposed at a rear portion of the swivel deck, a radiator disposed adjacent the engine, a driver's seat, a right implement controller disposed on the right side of the driver's seat and a left implement controller disposed on the left side of the driver's seat. A support frame is disposed at a rear portion of the swivel deck in such a manner as to create a rectangular space inside the swivel deck, the engine being mounted within the rectangular space. The driver' seat is disposed upwardly of the support frame. The right implement controller is secured to a right side of the support frame, and the left implement controller is attached to a left side of the support frame to be switchable in its posture between an operational posture and a retracted posture. An access step is disposed at a front portion of the support frame, and an access entrance is provided on a left side of the access step.