Cover with an acoustically isolated abutment

The casing cover (1) has a peripheral edge (2) that is profiled to receive an elastomer seal (3). An axial extension (7) is oriented in the direction of the engine block and is disposed at an inner portion of the edge of the casing cover. The extension is positioned to project axially beyond the edge surface of the casing cover. The extension extends beyond the sealing surface on the engine block when installed. A seal is provided at least on an outer surface of the extension, so as to provide a seal between the extension and the engine block when the cover is installed on the engine block.