Abstract: An internal combustion engine including an engine block having a top wall and a plurality of longitudinally aligned, spaced cylinders. A cylinder head has upper and lower walls with side walls extending therebetween. The cylinder head is mounted to the engine block with the lower walls sealingly opposing the top wall of the block so as to close the open ends of the cylinders. The cylinder head includes at least four passages associated with each of the cylinders extending through the cylinder head for delivering intake air to the associated cylinder and for removing exhaust gas from the associated cylinder. Each of these passages include an inlet, an outlet in fluid communication with the associated cylinder and a flow path extending therebetween. At least one of these passages includes a boss which is recessed in the passage and aligned with the inlet and which is adapted to receive a fastener employed to clamp the cylinder head to the engine block.

Abstract: The rocker arm cover on a diesel engine can be formed of a rigid molded plastic material to minimize the transmission of noise into the atmosphere. Sonic vibration of the cover can be reduced by reducing the cover material stiffness. The reduced stiffness of the cover material allows the roof area of the cover to be momentarily displaced away from the cylinder head in the presence of an acoustic wave, so that the roof area is not able to develop the restoring force that is necessary for vibrational motion.

Abstract: An oil pan for an internal combustion engine includes a body defining a reservoir for collecting engine coolant. The reservoir has a bottom and side walls extending upwardly from the bottom to present a flanged lip through which the oil pan may be mounted to the engine. An oil cooler assembly is housed within the body of the oil pan for cooling lubricant received from the engine. The body includes an oil inlet passage formed integrally therewith for receiving lubricant from the engine and delivering lubricant to the oil cooler. In addition, the body also includes an oil pick up passage formed integrally therewith for providing fluid communication between the reservoir and the engine through the flanged lip.