CARA KERJA SISTEM PENDINGIN PADA MESIN MOBIL

Summary

In this video, the process and importance of a car's engine cooling system are discussed. The video explains how coolant circulates through the engine, keeping the temperature within an optimal range (80-90°C). It covers key components like the thermostat, water jacket, and radiator, highlighting their roles in regulating temperature and preventing overheating. Additionally, it touches on how pressure and volume changes in the coolant are managed through the radiator cap and reservoir tank. The video concludes by emphasizing the importance of coolant circulation for maintaining engine performance.

Takeaways

• 😀 The engine operates best at a temperature range of 80°C to 90°C, ensuring optimal performance.
• 😀 A cooling system is essential to prevent the engine from overheating or running too cold, both of which can affect combustion and engine power.
• 😀 The coolant circulates within the water jacket, and its flow is controlled by the pump connected to the crankshaft.
• 😀 There are two stages of coolant circulation in the system, depending on the engine temperature: below and above 80°C to 90°C.
• 😀 Below 80°C to 90°C, the thermostat remains closed, and the coolant circulates only within the water jacket.
• 😀 When the engine reaches its operating temperature (80°C to 90°C), the thermostat opens, allowing coolant to flow into the radiator.
• 😀 The radiator helps to cool down the coolant by using airflow, which reduces its temperature and protects the engine from overheating.
• 😀 The coolant circulates from the water jacket to the radiator and back, maintaining the engine's optimal temperature.
• 😀 As the coolant heats up, its volume and pressure increase. The radiator cap manages this by using pressure and vacuum valves.
• 😀 The radiator cap’s pressure valve opens when the coolant pressure is too high, and the vacuum valve opens when the pressure decreases, pulling coolant back into the radiator.

Q & A

What is the role of the cooling system in a car engine?

The cooling system regulates the engine's temperature, preventing it from overheating or becoming too cold. This ensures optimal performance and prevents damage to the engine.

Why is it important for a car engine to operate at temperatures between 80°C and 90°C?

Operating at this temperature range allows the engine to perform efficiently and generate optimal power. If the engine gets too hot or too cold, the combustion process may be affected, reducing engine power.

What is the function of the thermostat in the cooling system?

The thermostat is a valve that regulates the circulation of coolant based on the engine's temperature. It controls whether the coolant circulates only within the engine's water jacket or also flows to the radiator for cooling.

How does the coolant circulate within the engine's cooling system?

The coolant is circulated by a pump that is powered by the engine's crankshaft. It moves through the water jacket, and when the engine reaches the optimal temperature, the coolant is directed to the radiator for cooling before returning to the engine.

What happens to the coolant when the engine reaches its optimal temperature?

When the engine's temperature reaches 80°C to 90°C, the thermostat valve opens, allowing coolant to flow from the water jacket to the radiator for cooling. This helps maintain the engine’s temperature by reducing the heat in the coolant.

How does the radiator help in cooling the engine?

The radiator cools the coolant by allowing it to pass through a core where air is blown over the fins. As the coolant flows from the top to the bottom of the radiator, the heat is transferred to the air, cooling the liquid before it returns to the engine.

What is the role of the radiator cap and the reservoir tank in the cooling system?

The radiator cap and reservoir tank are responsible for managing the pressure and volume of the coolant. When the coolant expands due to heat, the cap opens to release excess pressure into the reservoir. If the coolant volume decreases, the cap also allows coolant from the reservoir to return to the radiator.

What causes the coolant's pressure and volume to increase during operation?

As the coolant heats up, it expands, which increases its volume and pressure. This is a normal response due to the thermal properties of liquids, and it is managed by the radiator cap to prevent system damage.

How do the pressure and vacuum valves in the radiator cap work?

The pressure valve opens when the coolant pressure exceeds the system's safe threshold, allowing excess coolant to flow into the reservoir. The vacuum valve opens when the pressure drops, allowing coolant to return from the reservoir to the radiator, maintaining balance in the system.

What is the typical pressure range for the radiator cap in most car engines?

The typical pressure range for the radiator cap is between 0.9 kg/cm² and 1 kg/cm². This ensures that the coolant system operates within safe pressure limits to prevent leaks or overheating.