Patent ID: 9080497
Filing Date: 2015-07-14
Classification: F01P,F28F

Abstract:
1. A water-cooled engine, comprising: a cylinder-body-side water jacket disposed in a cylinder body that is coupled to a crankcase rotatably supporting a crankshaft and has a cylinder bore; a cylinder-head-side water jacket disposed in a cylinder head coupled to the cylinder body; a water pump configured to circulate cooling water between the cylinder-body-side and cylinder-head-side water jackets and a radiator, said water pump being disposed on an engine main body, wherein the cylinder-body-side and cylinder-head-side water jackets are configured such that the cooling water is allowed to flow in the water jackets independently of each other, a first connection path continuous with the cylinder-head-side water jacket connected to one of an inlet port and a discharge port of the water pump and a second connection path continuous with the cylinder-body-side water jacket connected to another of the inlet port and the discharge port are disposed in a sidewall of the cylinder body, said engine further comprising a thermostat valve configured to switch between a state in which the first and second connection paths communicate with each other and a state in which the first and second connection paths are connected to each other via the radiator, said thermostat valve being attached to the sidewall of the cylinder body; and a water-cooling oil cooler having a cooling water lead-in pipe configured to take in the cooling water and a cooling water lead-out pipe configured to lead out the cooling water is so attached to one sidewall of the engine main body as to protrude in a same direction as an actuation axis line of the thermostat valve, wherein the cooling water lead-in pipe is so connected to the thermostat valve as to communicate with the water jacket connected to the discharge port of the water pump, of the cylinder-body-side and cylinder-head-side water jackets, and the cooling water lead-out pipe is so connected to the thermostat valve as to communicate with the water jacket connected to the inlet port of the water pump, of the cylinder-body-side and cylinder-head-side water jackets.