An internal combustion engine is equipped with a water injector for cooling the internal combustion engine by a spray of atomized water into the intake track or combustion chamber prior to ignition. The atomized water spray may be in the intake manifold or directly in the cylinder. The water is injected at a volume of between a ratio of about 95% fuel to about 5% water and about 50% fuel and about 50% water. The temperature of the internal combustion engine is maintained at between about 95 C. and about 200 C. during operation.

An internal combustion engine is equipped with a water injector for cooling the internal combustion engine by a spray of atomized water into the intake track or combustion chamber prior to ignition. The atomized water spray may be in the intake manifold or directly in the cylinder. The water is injected at a volume of between a ratio of about 95% fuel to about 5% water and about 50% fuel and about 50% water. The temperature of the internal combustion engine is maintained at between about 95 C. and about 200 C. during operation.

A mechanical coolant pump for an internal combustion engine includes a pump housing defining an outlet volute, a first outlet channel comprising a first valve opening, a second outlet channel comprising a second valve opening, an impeller pump wheel, and an outlet valve arrangement. The second outlet channel is separate from and fluidically parallel to the first outlet channel. The impeller pump wheel pumps a liquid into the outlet volute. The outlet valve arrangement is fluidically upstream of the first outlet channel and the second outlet channel. The outlet valve arrangement comprises an integral valve body which pivots between an open position and a closed position. The valve body comprises a first retaining section and a second retaining section. When the valve body is in the closed position, the first retaining section completely closes the first valve opening and the second retaining section only partially closes the second valve opening.

A mechanical coolant pump for an internal combustion engine includes a pump housing defining an outlet volute, a first outlet channel comprising a first valve opening, a second outlet channel comprising a second valve opening, an impeller pump wheel, and an outlet valve arrangement. The second outlet channel is separate from and fluidically parallel to the first outlet channel. The impeller pump wheel pumps a liquid into the outlet volute. The outlet valve arrangement is fluidically upstream of the first outlet channel and the second outlet channel. The outlet valve arrangement comprises an integral valve body which pivots between an open position and a closed position. The valve body comprises a first retaining section and a second retaining section. When the valve body is in the closed position, the first retaining section completely closes the first valve opening and the second retaining section only partially closes the second valve opening.

A coolant pump includes an outlet volute comprising a pivot axis, an impeller pump, a housing, and an outlet valve arrangement. The housing comprises an outlet volute housing defining the outlet volute and comprises a volute housing wall comprising a recess, and a first outlet channel comprising a valve opening. The outlet valve arrangement is disposed in the first outlet channel and comprises a valve body which opens or closes the valve opening. The valve body comprises a circle segment body comprising a proximal surface and a maximum outside radius. The circle segment body is rotated around the pivot axis. The proximal surface is distant from the pivot axis by an offset distance which is at least of the maximum outside radius. The recess houses the circle segment body in the closed valve position. A lateral distance of the pivot axis to the volute housing wall is approximately equal to the offset distance.

A coolant pump includes an outlet volute comprising a pivot axis, an impeller pump, a housing, and an outlet valve arrangement. The housing comprises an outlet volute housing defining the outlet volute and comprises a volute housing wall comprising a recess, and a first outlet channel comprising a valve opening. The outlet valve arrangement is disposed in the first outlet channel and comprises a valve body which opens or closes the valve opening. The valve body comprises a circle segment body comprising a proximal surface and a maximum outside radius. The circle segment body is rotated around the pivot axis. The proximal surface is distant from the pivot axis by an offset distance which is at least of the maximum outside radius. The recess houses the circle segment body in the closed valve position. A lateral distance of the pivot axis to the volute housing wall is approximately equal to the offset distance.

A reserve tank includes a gas-liquid separator, a flow inlet portion, a flow outlet portion, and a projection shaped in a tubular form. The gas-liquid separator is shaped in a bottomed tubular form and is centered on a predetermined axis. The flow inlet portion is configured to conduct coolant into an inside of the gas-liquid separator. The flow outlet portion is configured to discharge the coolant from the inside of the gas-liquid separator. The projection extends along the predetermined axis from a bottom wall at the inside of the gas-liquid separator. An inner space of the projection opens to an inner space of the gas-liquid separator at a distal end portion of the projection.

A reserve tank includes a gas-liquid separator, a flow inlet portion, a flow outlet portion, and a projection shaped in a tubular form. The gas-liquid separator is shaped in a bottomed tubular form and is centered on a predetermined axis. The flow inlet portion is configured to conduct coolant into an inside of the gas-liquid separator. The flow outlet portion is configured to discharge the coolant from the inside of the gas-liquid separator. The projection extends along the predetermined axis from a bottom wall at the inside of the gas-liquid separator. An inner space of the projection opens to an inner space of the gas-liquid separator at a distal end portion of the projection.

In a water outlet, the deterioration of sealing performance is prevented by a sealing member sealing between a pipe and the connecting port of the water outlet. A water outlet is provided at a coolant outlet of an internal combustion engine to which a pipe leading coolant out of the engine is connected, having a dish-shaped body fixed to the engine, a cylindrical connecting port provided to rise outward from the body portion and to be inserted into the inside of the pipe, and a sealing member on the outer circumference of the connecting port. A convex portion is provided on the outer circumferential side of the connecting port to rise outward from the body, and an annular sealing member is provided between the connecting port and the pipe, and at least a circumferential portion of the pipe is disposed between the convex portion and the connecting port.