Abstract: A reservoir in which coolant is stored, is fluidly interposed between the downstream end of the condensor in which coolant vapor from the engine coolant jacket is condensed, and a coolant return pump which is responsive to a level sensor disposed in the coolant jacket, in a manner to form part of the cooling circuit of the system. The system further includes two temperature sensors, the first is disposed in the lower tank of the radiator and the other in the coolant jacket proximate the cylinder head. A device which modifies the pressure prevailing in the system is operated in response to one or both of the temperature sensors. This device can take the form of a cooling fan or an electromagnetic valve which controls one of a coolant jacket/atmosphere vent or a reservoir/atmosphere vent.

Abstract: In order to improve engine warm-up characteristics under cold climatic conditions and to safegard against possible unintentional overfilling of the of the cooling circuit of an evaporative type automotive cooling system wherein the coolant is permitted to boil and the vapor used as a vehicle for removing heat from the engine, the ambient temperature or a parameter which varies with the same is sensed and the control of the cooling system modified accordingly. One main feature comes in the control which is effected to reduce the surface area of the radiator of the system in which the coolant vapor is condensed is modified to avoid overfilling and possible damage due to overpressurization.

Abstract: In order to minimize the number of valves and conduits and the amount of coolant must be carried in an auxiliary reservoir of an evaporative type automotive cooling system, the valve and conduit arrangement which communicates the normally closed circuit cooling system with the reservoir consists of only two conduits and two valves. When the engine is stopped the cooling circuit is allowed to fill completely with the coolant from the reservoir. When the engine is started a low temperature non-condensible matter purge operation is avoided and if the temperature rises above a target value, either coolant is pumped out of the system (if excess coolant is available therein) or high temperature vapor is vented from the bottom of the radiator in bursts to purge out the non-condensible matter.

Abstract: An internal combustion engine comprises a cylinder block including a skirt section, and a plurality of bearing sections connected to the skirt section; and a bearing beam structure secured to the bottom part of the cylinder block and including a plurality of main bearing cap sections each associating with each cylinder block bearing section to rotatably support a crankshaft, first and second beam sections disposed to connect the main bearing cap sections with each other, and first and second side wall sections disposed to securely connect the bearing cap sections with each other respectively at their one of opposite side portions and at the other one of the opposite side portions, each side wall section being securely connected at its lower part with each beam section and the its top part with the lower part of the cylinder block skirt section, thereby greatly improving the rigidity of the entire bearing beam structure, thereby effectively suppressing noise emission from the cylinder block.