A coolant composition includes a viscosity improving agent and a base. The viscosity improving agent includes at least one nonionic surfactant and at least one anionic surfactant represented by the following Formula (1) of R.sup.1O(R.sup.2O).sub.m-SO.sub.3M. The base is formed of water and/or at least one alcohol selected from the group consisting of a monohydric alcohol, a dihydric alcohol, a trihydric alcohol, and a glycol monoalkyl ether. R.sup.1 represents a linear or branched alkyl group having 16 to 24 carbon atoms or a linear or branched alkenyl group having 16 to 24 carbon atoms, R.sup.2 represents an ethylene group or a propylene group, m represents an average addition molar number of R.sup.2O which is a number of 0.5 to 10, and M represents a cation or a hydrogen atom. A shear viscosity of the coolant composition is 8.5 mPa.Math.s or higher at 25 C. and is 2.0 mPa.Math.s or lower at 100 C.

A coolant composition includes a viscosity improving agent and a base. The viscosity improving agent includes at least one nonionic surfactant and at least one anionic surfactant represented by the following Formula (1) of R.sup.1O(R.sup.2O).sub.m-SO.sub.3M. The base is formed of water and/or at least one alcohol selected from the group consisting of a monohydric alcohol, a dihydric alcohol, a trihydric alcohol, and a glycol monoalkyl ether. R.sup.1 represents a linear or branched alkyl group having 16 to 24 carbon atoms or a linear or branched alkenyl group having 16 to 24 carbon atoms, R.sup.2 represents an ethylene group or a propylene group, m represents an average addition molar number of R.sup.2O which is a number of 0.5 to 10, and M represents a cation or a hydrogen atom. A shear viscosity of the coolant composition is 8.5 mPa.Math.s or higher at 25 C. and is 2.0 mPa.Math.s or lower at 100 C.

A control device for an internal combustion engine is provided which enables control of dilution of oil by fuel and water drops, i.e., control of the amount of so-called oil dilution. The control device for an internal combustion engine that is lubricated or cooled by oil includes: a variable displacement oil pump capable of varying the amount of discharge of the oil; an air-fuel ratio sensor for sensing an air-fuel ratio of the internal combustion engine; and an ECU for controlling the amount of discharge of the variable displacement oil pump. The ECU controls the amount of discharge of the variable displacement oil pump, based on the air-fuel ratio sensed by the air-fuel ratio sensor.

A control device for an internal combustion engine is provided which enables control of dilution of oil by fuel and water drops, i.e., control of the amount of so-called oil dilution. The control device for an internal combustion engine that is lubricated or cooled by oil includes: a variable displacement oil pump capable of varying the amount of discharge of the oil; an air-fuel ratio sensor for sensing an air-fuel ratio of the internal combustion engine; and an ECU for controlling the amount of discharge of the variable displacement oil pump. The ECU controls the amount of discharge of the variable displacement oil pump, based on the air-fuel ratio sensed by the air-fuel ratio sensor.

A cooling system may include a cooling pump, a cooling source, a thermal energy storage, a mixing valve, a recharge valve, a recharge pump. The mixing valve may be in fluid communication with a thermal load. A first input of the mixing valve may be in fluid communication with the thermal energy storage. A second input of the mixing valve may be in fluid communication with the recharge pump. Operation of the recharge pump may cause heated cooling fluid output from the thermal load to bypass the cooling pump and flow to the second input of the mixing valve. The recharge valve may be in fluid communication with the thermal energy storage and the cooling pump. The recharge valve may regulate a recharge fluid flow comprising cooling fluid received from the thermal energy storage.

An internal combustion engine includes: an oil filter that is mounted to a mounting surface formed on a crankcase and clarifies an oil flowing in; an oil cooler that is disposed on a front side of the crankcase, cools the oil flowing in from the oil filter and returns the oil into a flow path in the crankcase; and a bracket formed on a front wall of the crankcase and having the mounting surface. An outflow port through which the oil flows out toward the oil cooler and an inflow port through which the oil flows in from the oil cooler are disposed in the bracket. Accordingly, in the internal combustion engine, routes of oil passages can be simplified as much as possible.

An object is to provide a type of device capable of properly cooling a bearing of a throttle body even under a condition that the throttle body receives heat of high-temperature intake air or exhaust gas. In the present invention, an engine coolant passage that guides a coolant of an engine is provided integrally with a member fixing a bearing to be adjacent to a circumferential wall of the bearing of the member fixing the bearing, which supports a throttle shaft, and heat transferred from the bearing (or likely to be transferred to the bearing) via the member fixing the bearing is carried away to the outside of a throttle body by the engine coolant.

A temperature responsive valve includes a housing and a cylindrical structure disposed within the housing. The housing defines an inlet passageway and an outlet passageway wherein the cylinder body of the cylindrical structure is disposed between the inlet passageway and the outlet passageway. The cylindrical structure includes a first layer so that the cylindrical structure is configured to expand from a decreased diameter to an increased diameter when the first layer of the cylindrical structure is exposed to an increased pre-determined temperature range causing the cylindrical structure restricts the inlet passageway and the outlet passageway at such increased pre-determined temperature range.

A temperature responsive valve includes a housing and a cylindrical structure disposed within the housing. The housing defines an inlet passageway and an outlet passageway wherein the cylinder body of the cylindrical structure is disposed between the inlet passageway and the outlet passageway. The cylindrical structure includes a first layer so that the cylindrical structure is configured to expand from a decreased diameter to an increased diameter when the first layer of the cylindrical structure is exposed to an increased pre-determined temperature range causing the cylindrical structure restricts the inlet passageway and the outlet passageway at such increased pre-determined temperature range.

There is provided a motorcycle. A side stand is disposed at a side-lower portion of an engine and configured to be rotatable between a using position at which the side stand can be grounded to a ground surface and a retraction position at which the side stand cannot be grounded to the ground surface. An inflow piping is configured to supply cooling water delivered from a water pump to a supercharger. An outflow piping is disposed above the supercharger and configured to return the cooling water having cooled the supercharger to the water pump. The outflow piping is provided to be horizontal or to have an upward gradient from an upstream side toward a downstream side in a state where the side stand is displaced to the using position to be grounded to the ground surface and the engine is inclined toward the side stand-side.