Engine cooling system

An engine cooling system comprising:

• a main intake line for supplying external air to an intake manifold attached to an engine comprising a cylinder block and a cylinder head;
• a supplementary intake line branched from one side of the main intake line and joined to the other side of the main intake line;
• an intake route control valve provided in the main intake line;
• a main exhaust line for flowing exhaust gas from an exhaust manifold provided in the cylinder block;
• an exhaust route control valve provided in the main exhaust line;
• a turbocharger including:
• a turbine housing and a turbine wheel to be rotated by the exhaust gas flowing in the supplementary exhaust line,
• a compressor housing and a compressor wheel to be rotated by rotation force of the turbine wheel and supercharging intake air flowing in the supplementary intake line,
• a shaft connecting the turbine wheel and the compressor wheel, and
• a bearing for rotatably supporting the shaft;
• an intercooler mounted to the supplementary intake line on a downstream side of the turbocharger;
• an exhaust gas recirculation (EGR) cooler branched from the exhaust manifold for recirculating the exhaust gas and provided in an EGR line connected to the main intake line;
• and
• a cooling line for flowing a coolant supplied from a water pump to cool the EGR cooler, the exhaust route control valve, and/or the turbine housing.