Abstract: An internal-combustion engine with a hydraulic device (1) for rotation angle adjustment of a camshaft (2) relative to a crankshaft is provided and includes a rotor with an impeller form (7), which is rotationally fixed via a central fastener (6) to the camshaft, and a stator (4), which rotates synchronously with a drive wheel (3) driven by the crankshaft, wherein on both sides of the impeller blades of the rotor, there are pressure chambers, which are each limited by radial walls of the stator (4) and can be filled with and emptied of hydraulic fluid via a hydraulic system, wherein the hydraulic fluid is guided, on one hand, via an annular gap (13) between rotor (7) and the central fastener (6) and, on the other hand, through generally axial and radial channels into the pressure chambers.