a camshaft adjusting device for an internal combustion engine is provided . a functionally reliable camshaft adjusting device designed for a long - lasting operation is obtained when the camshaft adjuster has a lifelong lubrication located in the housing sealed from the surrounding area be sealing covers . the camshaft adjuster is not required to be mounted inside the cylinder head , but can be mounted as a separate unit on the cylinder head of the internal combustion engine independent of the lubricating oil circuit . this expands , in particular , the range of possibilities for use of the camshaft adjuster with a belt drive .