Abstract: A combined cylinder block and crankcase for a multi-cylinder light-metal alloy internal-combustion engine has partitioning walls between the cylinders. The cylinders are surrounded by cooling-water channels. Combustion cylinder spaces are disposed between the combined cylinder block and crankcase and a cylinder head. In order to ensure that during the operation of the internal-combustion engine the cylinder diameters (adjacent to the combustion spaces) are kept within fixed tolerances specifically in the area of the partitioning walls, thermal-expansions slots are provided in the partitioning walls which lead to the cooling-water channels. These thermal-expansions slots are sealed off with respect to the cooling-water channels so that the partitioning walls are not impaired by cavitation.

Abstract: A control installation for the feedback of exhaust gases, in which two adjusting valves are built into the feedback line in parallel to one another; the two adjusting valves are controlled by a three-way electric shifting valve which is actuated by a pressure sensor connected to the suction line, in such a manner that at lower engine loads, only one adjusting valve is opened whereas at higher engine loads, both adjusting valves are opened.