Engine cooling is one of the systems that helps your engine work. Internal combustion engines turn most of the energy from combustion into waste heat. While most of that is sent out through the exhaust, a significant amount of heat remains. Our engines are generally air cooled, so logic suggests that more air equals better cooling. Consequently, the nacelle contains ducts and baffles that direct air flow evenly across the engine’s cooling surfaces, thus keeping the engine’s operating temperature balanced. If these baffles are removed or damaged, excessive heat buildup in part of the engine can lead to additional wear and possibly failure.
Outside air aids in cooling the engine.
In addition to cooling, an engine needs air and fuel. An intake manifold guides the mixture into the cylinder and fuel is added via the carburetor or fuel injectors. The carburetor remains the most common solution. Carburetors are the older technology but have the advantage of being a well-tested, less complex, and very reliable solution.
Fuel injection allows greater control and greater efficiency, but is more complex. Carburetors do have one distinct disadvantage: carburetor icing can choke the engine. Carb heat is a simple solution to this specific problem, but you do have to activate it.
Then there’s the exhaust system, which transfers the spent gases and heat out of the cylinder. The exhaust system ushers the hot combustion gases safely out of the engine compartment and into a muffler. Despite its humble description, the exhaust system is absolutely safety critical. For more information, take a look at the article, “(Un) Holy Smoke! The Nightmare of Smoke, Fire, and Deadly Gas,” in our September/October 2019 issue at https://adobe.ly/34ckY59.
One way to get more power from an engine is to increase the amount of air and fuel in the cylinder during combustion. This can be done through forced induction, more commonly called turbocharging or supercharging. Turbocharging is more common in today’s GA airplanes, but both techniques essentially do the same thing. They compress intake air to force more air and fuel into the engine than normal atmospheric conditions will allow. The difference is that turbocharging uses the engine’s exhaust gases to power the compressor while a supercharger taps the engine’s power output. For more information on forced induction, see “The Bigger Bang Theory” in our May/June 2015 issue (p.26) at go.usa.gov/xpPxz.