What is a Water-Cooled Engine?

 What is a Water-Cooled Engine?

When an internal combustion engine is liquid or water-cooled, it is referred to as a liquid or water-cooled engine. Latest high-end motorcycles, with the exception of cars and other commercial vehicles, use water/liquid-cooled engines. A water-cooled engine is very similar to a water-cooled engine. There are subtle differences.

Liquid-cooled engines also use water as the main raw material. Older generation engines only use pure water/distilled water to cool the engine. After that, manufacturers began to use coolants instead of water. After that, it became popular as an air-cooled engine. The coolant is an approximately 1:1 mixture of water and concentrated coolant. Manufactures coolant mixtures for engine cooling systems. Most modern engines use a pressurization/shutdown system to effectively control engine temperature.

Role of Coolant in Engines

Coolants contain additives such as antifreeze and corrosion inhibitors. Therefore, the coolant prevents the water from freezing in extreme weather conditions. It also prevents engine damage. Rust inhibitors prevent engine parts such as cylinder blocks and heads from rusting when they come into contact with water. It also helps prevent corrosion and extends the life of engine components, especially aluminum. Refrigerants also help raise the boiling point of water.

Role of Thermostat in Water Cooled Engine

Water-cooled engine uses thermostats to effectively control temperature. When the engine cools, the thermostat bypasses the radiator. It then circulates cooling water inside the engine to quickly reach normal engine operating temperature. When the coolant temperature rises above a certain level (usually over 100 degrees Celsius), the thermostat opens and coolant flows into the radiator to cool it down. The water flows from the upper radiator tank through capillaries to the lower tank surrounded by fins. In addition, a cooling fan blows air over the ribs. This is how it transfers heat from the water to the air flowing past.

Water Cooled Engine with closed circuit

Liquid/water cooled engines use a pressurized shut-off system. The pressurization system helps raise the boiling point of water to over 110°C. Therefore, the water does not evaporate immediately and can be used for a long time. Heat from hot engine components such as cylinder heads and blocks. It is discharged by circulation of water. A cooling fan cools the water as it flows through the radiator.

Water cooled Engine Construction

The water jacket is stamped into the cylinder head and cylinder block. This helps the water reach the hottest surface inside the engine and efficiently dissipate heat. The larger the surface area that comes into contact with the water, the more heat the water gives off. Also, the water-cooled engine uses a water pump to increase water flow. The water flows freely into the engine and effectively dissipates excess heat.


1. Very effective for multi-cylinder engines.

2. Effectively control the temperature of the motor.

3. Improve the thermal efficiency of the motor and prevent overheating.

4. Closed system reduces water loss through evaporation

5. Use coolant for most weather conditions

6. Water jacket reduces engine noise


1. Complex design

2. Higher manufacturing costs

3. Many parts

4. High maintenance costs


Related post