Cooling system of engine

1. A cooling system of an engine comprising:

a cylinder liner formed in a hollow cylindrical shape and pressed against an inside of a cylinder of the engine;

a block coolant jacket positioned in an outside of the cylinder liner in a radial direction to cool a cylinder block;

the cylinder block provided with the cylinder liner and the block coolant jacket therein; and

a cylinder head engaged on the cylinder block, including an exhaust port and an intake port fluidically-communicated with a combustion chamber and respectively formed at an exhaust side and an intake side of the cylinder head, and provided with a head coolant jacket inside of the cylinder head,

wherein the block coolant jacket includes:

an upper coolant jacket formed in a shape covering an upper portion of the cylinder liner; and

a lower coolant jacket formed in a shape covering a lower portion of the cylinder liner and separated from the upper coolant jacket, and

wherein a division wall is disposed between the upper coolant jacket and the lower coolant jacket and prevents coolant from directly communicating between the upper coolant jacket and the lower coolant jacket in the cylinder block throughout an entire body of the division wall.

2. The cooling system of the engine of claim 1 , wherein the upper coolant jacket includes:

an exhaust side upper coolant jacket formed at the exhaust side; and

an intake side upper coolant jacket formed at the intake side, and

wherein a coolant discharged from a coolant pump sequentially passes through the exhaust side upper coolant jacket, the head coolant jacket, and the intake side upper coolant jacket.

3. The cooling system of the engine of claim 2 , wherein the lower coolant jacket includes:

an exhaust side lower coolant jacket formed at the exhaust side; and

an intake side lower coolant jacket formed at the intake side, and

wherein the coolant passing through the exhaust side upper coolant jacket, the head coolant jacket, and the intake side upper coolant jacket sequentially passes through the intake side lower coolant jacket and the exhaust side lower coolant jacket to execute cooling thereof.

4. The cooling system of the engine of claim 3 , wherein the coolant discharged from the coolant pump sequentially passes through the exhaust side upper coolant jacket, the head coolant jacket, the intake side upper coolant jacket, the intake side lower coolant jacket, and the exhaust side lower coolant jacket is circulated to the coolant pump to perform cooling thereof.

5. The cooling system of the engine of claim 2 , further comprising a coolant control module disposed in a coolant line connected from the intake side upper coolant jacket to the intake side lower coolant jacket to control flow of the coolant.

6. The cooling system of the engine of claim 5 , wherein the coolant control module distributes the coolant to at least one of:

a radiator to radiate a heat of the coolant;

an EGR cooler to control temperature of recirculating exhaust gas;

an oil cooler to control an oil temperature of the engine;

a transmission oil cooler to control oil temperature of a transmission; and

a heater disposed for an indoor heating, and

the coolant control module controlling distributed coolant.

7. A cooling system of an engine comprising:

a cylinder liner formed in a hollow cylindrical shape and pressed against an inside of a cylinder of the engine;

a block coolant jacket positioned in an outer side of the cylinder liner in a radial direction to cool a cylinder block;

the cylinder block provided with the cylinder liner and the block coolant jacket therein; and

a cylinder head engaged on the cylinder block, including an exhaust port and an intake port fluidically-communicated with a combustion chamber and respectively formed at an exhaust side and an intake side of the cylinder block, and provided with a head coolant jacket inside the cylinder block,

wherein the block coolant jacket includes:

an exhaust side upper coolant jacket formed at the exhaust side;

an exhaust side lower coolant jacket formed under the exhaust side upper coolant jacket;

an intake side upper coolant jacket formed at the intake side; and

an intake side lower coolant jacket formed under the intake side upper coolant jacket, and

wherein the coolant executes the cooling while sequentially passing through the exhaust side upper coolant jacket, the head coolant jacket, the intake side upper coolant jacket, the intake side lower coolant jacket, and the exhaust side lower coolant jacket, and

wherein a division wall is formed between the exhaust side upper coolant jacket and the exhaust side lower coolant jacket, and between the intake side upper coolant jacket and the intake side lower coolant jacket, and prevents coolant from directly communicating between the exhaust side upper coolant jacket and the exhaust side lower coolant jacket and between the intake side upper coolant jacket and the intake side lower coolant jacket throughout an entire body of the division wall.

8. The cooling system of the engine of claim 7 , wherein a coolant pump pumps the coolant to the exhaust side upper coolant jacket.

9. The cooling system of the engine of claim 7 , further comprising a coolant control module to control a flow of the coolant exhausted from the intake side upper coolant jacket.

10. The cooling system of the engine of claim 9 , further comprising a branch line branched from a coolant line formed between the intake side upper coolant jacket and the coolant control module and connected to the intake side lower coolant jacket.

11. The cooling system of the engine of claim 10 , wherein the branch line includes a control valve disposed to control the flow of the coolant.

12. The cooling system of the engine of claim 7 , wherein the block coolant jacket is formed along an outer surface of the cylinder liner.