CoolantThailand
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158. Coolant
Coolant is a fluid that circulates through a vehicle's cooling system to remove excess heat from the engine or other components. It usually contains water mixed with antifreeze and corrosion inhibitors so that the cooling system can operate safely across a wide range of temperatures.
The coolant level should be checked according to the vehicle manufacturer's instructions. The correct coolant specification must be used, and the cooling system should only be opened when it is safe to do so because hot coolant can be under pressure.
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What does engine coolant do?
Coolant absorbs heat from the engine and carries it to the radiator, where the heat can be released. It also helps protect the cooling system against freezing, corrosion and excessive temperatures.
Can you use any type of coolant?
No. Vehicles can require different coolant specifications and mixtures. Drivers should use coolant that meets the vehicle manufacturer's requirements and avoid mixing incompatible coolant types.
Should you open the coolant reservoir when the engine is hot?
No. A hot cooling system can be pressurised and opening it can release hot coolant or steam. Allow the system to cool and follow the vehicle manufacturer's instructions before opening the reservoir.

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