A pressurized cooling system has the advantage of which of the following?

• A. Reducing energy use
• B. Raising the boiling point of the coolant
• C. Increasing compression ratio
• D. Improving exhaust flow

Answer: (B)

Raising the boiling point of the coolant. When the cooling system is sealed and pressurized, the coolant is kept at a higher pressure, and water’s boiling point increases. This allows the coolant to reach higher temperatures without boiling, so the engine can run hotter without boiling over. Keeping the coolant liquid improves heat transfer to the radiator and reduces the formation of vapor pockets that can disrupt circulation, especially under heavy load. The other ideas aren’t direct benefits of pressurizing the cooling system—they relate to engine design or exhaust, not how the cooling system handles heat.