An engine cooler capable of suppressing a piston slap sound is provided. The engine cooler includes a cylinder block including a cylinder barrel and a water jacket, and a spacer stored in the water jacket, the water jacket surrounds the cylinder barrel, and the spacer encloses the cylinder barrel. Given that a width direction of the cylinder block is a lateral direction, a pressed member is pressed between the cylinder barrel and the spacer on lateral sides of the cylinder barrel, and a lower end of the pressed member is disposed above a lower end of each of right and left skirts of a piston located at a top dead center.

Methods and systems are provided for a water jacket diverter. In one example, the water jacket diverter has a continuous upper rail with a profile including curved and linear portions where the profile of the upper rail is optimized to moderate coolant flow through the water jacket. The water jacket diverter further includes at least one protrusion extending outwards from an outer face of the diverter, the at least one protrusion positioned in front of a coolant inlet.

Methods and systems are provided for a water jacket diverter. In one example, the water jacket diverter has a continuous upper rail with a profile including curved and linear portions where the profile of the upper rail is optimized to moderate coolant flow through the water jacket. The water jacket diverter further includes at least one protrusion extending outwards from an outer face of the diverter, the at least one protrusion positioned in front of a coolant inlet.

A cylinder liner for internal combustion engines has an outer roughened surface that has particularly good adherence properties. The surface has is covered with protrusions or spines of varying shapes and sizes, which are created by spraying the mold with a coating and then casting the cylinder liner in the mold. The spines are generally conical or needle-shaped, with the bases being larger than the tips. The spines have an aggregate cross-sectional surface area measured at 0.2 mm from a ground cylindrical surface that is between 50-90% of the total ground cylindrical surface area, and an aggregate cross-sectional surface area measured at 0.4 mm from the ground cylindrical surface that is between 20-45% of the total ground cylindrical surface area.

A cooling structure of a multi-cylinder engine is provided. The engine has cylinders and a cylinder block formed with a cylinder bore wall. The cooling structure includes a water jacket formed in the cylinder block and defined by the cylinder bore wall and a jacket outer surface surrounding the cylinder bore wall, a water pump for feeding a coolant to the water jacket, an introduction portion formed in the cylinder block, having an introduction port opening to the jacket outer surface, and for introducing the coolant to the water jacket, and a spacer member accommodated inside the water jacket. The spacer member has a spacer main body surrounding the cylinder bore wall, and a dividing wall protruding toward the jacket outer surface from an outer circumferential surface of the spacer main body. The dividing wall extends in a circumferential direction at a position opposing the introduction port.

A cooling structure of a multi-cylinder engine is provided. The engine has cylinders and a cylinder block formed with a cylinder bore wall. The cooling structure includes a water jacket formed in the cylinder block and defined by the cylinder bore wall and a jacket outer surface surrounding the cylinder bore wall, a water pump for feeding a coolant to the water jacket, an introduction portion formed in the cylinder block, having an introduction port opening to the jacket outer surface, and for introducing the coolant to the water jacket, and a spacer member accommodated inside the water jacket. The spacer member has a spacer main body surrounding the cylinder bore wall, and a dividing wall protruding toward the jacket outer surface from an outer circumferential surface of the spacer main body. The dividing wall extends in a circumferential direction at a position opposing the introduction port.

A cylinder block for an engine includes a cylinder liner and a water jacket through which a coolant flows, the water jacket being formed along a circumference of the cylinder liner, where an insulation coating layer made of a polyamideimide resin and an aerogel dispersed in the polyamideimide resin may be formed at an external circumferential surface of the cylinder liner.

A cylinder block for an engine includes a cylinder liner and a water jacket through which a coolant flows, the water jacket being formed along a circumference of the cylinder liner, where an insulation coating layer made of a polyamideimide resin and an aerogel dispersed in the polyamideimide resin may be formed at an external circumferential surface of the cylinder liner.

The present disclosure provides a split cooling apparatus for an internal combustion engine, the apparatus including: a base inserted into a water jacket of a cylinder block, the base surrounding an outside of a cylinder along a shape of the cylinder; an insertion groove formed on the base by being depressed into an inner surface of the base; and a sealing member inserted into the insertion groove, wherein when a temperature of cooling water supplied into the water jacket reaches a preset temperature or higher, the sealing member expands so as to close a flow passage between the base and the cylinder, thereby increasing flow resistance of the cooling water and thus reducing a heat transfer rate of the cylinder.

A cooling structure of a multi-cylinder engine is provided, which includes a water jacket formed in a cylinder block to surround cylinder bores of cylinders arranged inline, a spacer, and a coolant inlet. The spacer includes openings at positions corresponding to inter-cylinder-bore portions and a rectifying part extending outwardly on a lower side of the openings. The rectifying part inclines continuously upwardly while extending in one of an exhaust- and intake-side section of the jacket from a first end side to a second end side that is the opposite side from the first end side in a cylinder line-up direction, extending on the second end side from the one of the exhaust- and intake-side sections to the other one of the exhaust- and intake-side sections, and then extending from the second end side to the first end side in the other one of the exhaust- and intake-side sections.