Cooling circuit for motor vehicle internal combustion engine includes water pump that enables circulation of cooling water, with water bypassing radiator and circulating in lower water chamber during cold-starting

摘要

The cooling circuit includes a cylinder head water jacket including two interconnected parts, i.e. a lower water jacket (3), and an upper water jacket (3') that is connected to the vehicle's radiator (5). A cylinder housing water jacket (2) is connected to the lower water jacket (3), and a water pump (1) placed upstream of the engine assures circulation of cooling fluid. The output of the pump is connected to the lower water jacket or the cylinder housing water jacket (2) so that cooling fluid can be circulated while by-passing the radiator, e.g. when cold-starting the engine.