Abstract: An exhaust-gas recirculation module for an internal combustion engine includes an outer housing, an exhaust-gas cooler comprising an inner housing arranged within the outer housing, an exhaust-gas recirculation valve arranged upstream of the exhaust-gas cooler, an exhaust-gas duct formed in the outer housing arranged upstream of the exhaust-gas recirculation valve, and a coolant channel arranged between the inner housing and the exhaust-gas duct.

Abstract: A spacer arranged inside a water jacket which is formed to surround peripheries of cylinder bores in a cylinder block of an internal combustion engine includes support legs extending in an up-and-down direction from a spacer main body part which partitions the water jacket into an upper and lower cooling water passages. The support legs are disposed in opposite end portions in a cylinder row line direction, where the temperatures of the cylinder bores tend to be lower. Accordingly, even if the flow of cooling water is more or less inhibited by the support legs and the cooling effect deteriorates, it is possible to prevent the temperatures of the respective cylinder bores from becoming different by suppressing the influence to a minimum.

Abstract: A cylinder block side drain is provided in a cylinder block and a crankcase side drain is provided in a crankcase. A jacket cover is provided in an water jacket of the cylinder block. The jacket cover is pressed against the wall of the water jacket on the crankcase side. When discharging the coolant, the water jacket is opened by pushing the jacket cover inward using a coupler and the coolant is discharged to the outer side of the crankcase via the coupler.

Abstract: A spacer covets intermediate portions of respective cylinder bores in a depth direction of a water jacket throughout the entire peripherics of the intermediate portions in the peripheral direction. Accordingly, the intermediate portion of each cylinder bore becomes higher in temperature than any other portion, and is thermally expanded. Thereby, the clearance between the cylinder bore and the corresponding piston increases. Thus, the friction decreases to improve fuel efficiency of an internal combustion engine. Furthermore, the temperature of oil lubricating the intermediate portion of the cylinder bore rises, and the viscosity decreases. Accordingly, the effect of friction reduction is enhanced more. Furthermore, upper and lower portions of the cylinder bores in a cylinder axis direction are sufficiently cooled. Therefore, the cooling performance of a top part and a skirt part of each piston, which tends to become higher in tempera lure, is secured. Accordingly, overheat can be prevented.

Abstract: The invention discloses a general-purpose gasoline engine, comprising a cylinder block, a cylinder head main body (1), and an intake passage (12) and an exhaust passage (11) arranged on the cylinder head main body (1); an intake valve (5) is arranged on the cylinder head main body (1) correspondingly to the intake passage (12), an exhaust valve (9) is arranged correspondingly to the exhaust passage (11), the intake valve (5) is correspondingly provided with an intake rocker arm (8) and an intake push rod, the exhaust valve (9) is correspondingly provided with an exhaust rocker arm (2) and an exhaust push rod, a combustion chamber surface (13) is formed on the inner side of the cylinder head main body (1), and the combustion chamber surface (13) is of a spherical structure or an arch structure formed of smooth curves; the part of the combustion chamber surface (13) between the intake valve (5) and the exhaust valve (9) forms a nose bridge region (14), and a through air-cooling passage (10) is arranged on the c

Abstract: An air-cooled engine is provided, in which a cooling fan assembly for inducing a stream of cooling air and a screen member for covering an axial end face of the cooling fan on a suction side are drivingly mounted on a rotary drive shaft of the engine. A fan casing covering the cooling fan assembly and defining an air flow path for the flow of the stream of cooling air is formed with an air intake opening through which the cooling air is introduced towards the cooling fan assembly and the screen member. A cutter is formed in an outer peripheral portion of the screen member or its neighbor so as to protrude axially close to an inner surface of the fan casing at a position downstream of the cooling air from the air intake opening.

Abstract: The purpose of the present invention is to improve cooling efficiency of a cylinder head of an air-cooled engine. With regard to the construction that a cooling fan is provided at one of ends of a crankshaft, and cooling air from the cooling fan is guided to a cylinder head 4 so as to cool the cylinder head 4, an intake manifold 8 is arranged above the cooling fan, a duct 51 is provided at the lateral center of the intake manifold 8 so as to suck air from an air cleaner, cooling air is sent from both sides of the duct 51 to an intake valve, an exhaust valve and an injection nozzle arranged in the cylinder head 4, and a shielding plate 55 is provided at one of lateral sides of the duct 51.

Abstract: An improved engine for aeronautical applications includes a forged cylinder block having a drive device rotatably mounted therewithin and a motive device for rotating the drive device, the motive device including two cylinder banks in a V-type configuration and a plurality of cylinders mounted within the cylinder banks for producing power and rotating the drive device. The forged cylinder block further includes a plurality of cylinder cavities formed in the cylinder banks and the upper approximately one-third of each of the cylinder cavities is generally surrounded by a generally toroidal cooling chamber, and the lower approximately two-thirds of each of the cylinder cavities is generally free of any surrounding cooling chambers. Finally, a coolant circulation device in fluid transmission connection with each of the cooling chambers is operative to circulate cooling fluid therethrough whereby the upper approximately one-third of each of the cylinder cavities is cooled by the cooling fluid.

Abstract: The disclosed multi-cylinder, poppet-valved engine, has replacement cylinder sleeves larger than the original sleeves, and laterally supported near their upper ends by an aluminum alloy plate having a continuous flange or boss projecting into the cylinder block. The flange has an inner perimeter surface having a profile fittingly engaging upper exterior cylindrical surfaces of the sleeves providing lateral support to the sleeves and heat transfer from the sleeves to coolant and to the block. The flange further provides a coolant groove that circulates coolant around the perimeter of the cylinder sleeves to further the heat transfer from the sleeves to the coolant and to the block. The plate is sealed to the block and head with a spacing and gasketing to accommodate thermal expansion while avoiding combustion gas leakage at the cylinder sleeve tops.

Abstract: In an outboard engine system, a first opening communicating with a cooling water discharge passage and a second opening communicating with a cooling water supply passage are formed adjacent to each other in an upper wall of a cooling water passage forming member. A relief valve is provided in a first opening at a position remote from a tilt shaft. The relief valve includes a valve seat provided at the upper wall and facing downward. A valve body is seated on the valve seat from below. Accordingly, any cooling water staying in an upper portion of the relief valve leaks through gaps between the valve seat and the valve body to be discharged easily. When the outboard engine system is tilted upward about the tilt shaft, the opening provided with the relief valve is moved upward so that the cooling water is discharged smoothly through the other opening.