Air Cooled vs Liquid Cooled Internal Combustion Engine

Basics

• This page compares air cooled, and liquid cooled ICE's

Air Cooled

Advantages

• Simplicity (no coolant, no coolant pump + other parts in the system)
• Lower Mass
• Less Space Taken Up

Disadvantages

• May require design focused on this (cooling fins, airflow etc)
• In systems without active airflow, once not moving (ie car is at a stoplight) most cooling goes away
• Harder to intentionally move heat around (for cabin heating, Engine Heat Recovery etc

Liquid Cooled

Advantages

• Higher Amount of Heat Can Be Moved (higher potential power + possible lower emmisions)
• More consistant (assuming compared to passive air cooling)
• Makes moving heat around easier (pump fluid where heat is needed, then simple air-liquid heat exchanger)
• Allows for easier Intercoolers ?

Disadvantages

• Added complexity
• Needs some sort of cooling fluid
• If fluid is lost catastrophically, it can damage the engine
• Added mass + space taken up

External Links

• The Wikipedia Page on Internal Engine Cooling