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Q: Reservoir coolant boiling.

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Sometimes the coolant in the reservoir starts to boil.I check the hoses and they aren't hot or stiff from too much pressure. Also, the temperature falls within good operating temperatures.

A: Hello! The cooling system removes a lot of ...

Hello! The cooling system removes a lot of heat from the engine and this process can create a lot of pressure. Expansion tanks or coolant reservoirs are designed into many of these systems. These tanks are used to bleed off extra pressure beyond the systems maximum safe limits and the fluid is able to escape into these tanks. Have a mechanic, like the ones at YourMechanic, inspect the cooling system to ensure proper cooling system fluid level and operation.

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