Abstract: In a forced-circulation type water-cooling system for a horizontal internal-combustion engine, a radiator is located roughly at the same height as an engine body in a surrounding space outside a cylinder head and is positioned at a lateral side of the engine body of the horizontal internal-combustion engine. A cooling water inlet for a water jacket and a pump mounting seat for a water pump are provided at one of the front and back opposite sides of the cylinder head, at the same side as where an engine a rotation shaft such as crankshaft of the engine or a gear casing thereof projects from one of the front and back opposite sides of the engine body. The water pump is mounted on the pump mounting seat with its pump shaft extending in the fore and back direction. A pump driving wheel is fixedly secured to the engine rotation shaft, and a pump input wheel is fixedly secured to the pump shaft. The pump driving wheel and the pump input wheel are interlockingly connected to each other through a wrapping connector.

Abstract: In a waste heat recovery system for a liquid-cooled internal combustion engine, including a water jacket of a liquid-cooled internal combustion engine in which a portion of the heat generating in the engine is absorbed by an engine cooling liquid, a first heat exchanger is provided for heat absorption from the exhaust gas in which the exhaust gas heat is absorbed thereby and a second heat exchanger is provided for heat recovery in which the waste heat is recovered from the engine cooling liquid carrying the above-mentioned heat. A second circuit for waste heat recovery from the engine includes the first heat exchanger and the second heat exchanger, both being connected to the water jacket in series. The second circuit is adapted to return the engine cooling liquid within the water jacket to the water jacket through the first heat exchanger and the second heat exchanger by a forced circulation force or a natural circulation force.

Abstract: In a waste heat recovery system for a horizontal liquid-cooled internal combustion engine, the engine heat absorbed by the engine cooling liquid in a water jacket and the exhaust gas heat absorbed thereby in a heat exchanger for heat absorption from the exhaust gas (a first heat exchanger) are adapted to be recovered from the engine cooling liquid in a heat exchanger for waste heat recovery (a second heat exchanger). The first heat exchanger and the second heat exchanger are located on the upper side of the engine body of the internal combustion engine. And the engine cooling liquid outlet of the water jacket and the engine cooling liquid inlet of the first heat exchanger are communicated with each other directly, and the engine cooling liquid outlet of the first heat exchanger and the engine cooling liquid inlet of the second heat exchanger are communicated with each other directly.