Engine cooling system

An engine cooling system for cooling a cylinder head and a cylinder block separately, the engine cooling system comprising:

• a cylinder block having cylinders arranged from a front side to a rear side of an engine with a block water jacket formed therein around the cylinders;
• a cylinder head fastened to a top side of the cylinder block with a head water jacket formed therein from the front side to the rear side of the engine;
• a water pump mounted to a front side of the cylinder block for pumping coolant to a front of the block water jacket;
• a coolant control valve arranged in a rear side of the cylinder block and the cylinder head to have a first end connected to a rear end of the block water jacket and a second end connected to a rear end of the head water jacket for having the coolant supplied thereto;
• a block cross drill hole formed in the block water jacket between cylinder bores for connecting the block water jacket from the intake side to the exhaust side;
• and
• a block packing of a predetermined length of a pipe shape inserted in each of a front side and a rear side of the block water jacket by a pressure from a top side to a lower side of the block water jacket to a predetermined distance for making the coolant flow through the block cross drill hole,
• wherein a connection passage is formed between a top side rear end of the block water jacket and a bottom side rear end of the head water jacket for supplying the coolant supplied to the block water jacket to the head water jacket.