Types of Engine Cooling

Liquid vs Air Cooling

Most car engines today are liquid-cooled, meaning they use a liquid coolant to absorb heat and dissipate it through a radiator. The most common form of cooling is with water, but there are other coolants like propylene glycol which can increase engine performance in hot weather or when the car is at high RPMs for long periods of time. What you may not know though is that some engines actually use both!

The reason for this is that water does not evaporate well at high temperatures so after prolonged RPMs or hot weather driving, the coolant can become too thick to circulate properly. To combat this problem, some engines use a mixture of water and antifreeze which does not evaporate as quickly when hot and can maintain proper circulation even after prolonged high RPMs or intense heat from the sun. Antifreezing also helps lower temperatures below what the engine could reach without additional cooling like a radiator or body of the car.

Twin Cooling Systems

On top of that, some engines actually have two radiators in order to keep coolant separated. This is called a “twin-cooling” system and can help prevent leaks because of how close the two radiators are together. Twin cooling systems are common on diesel engines as well as some V8s which use both heads for cooling instead of one.

The main difference between the two types of coolants is that water has rust inhibitors, while antifreeze does not. Antifreeze also contains extra additives like glycolytic acid which helps to prevent corrosion in the system.

Despite what you may have heard, both coolants can be used in your car at the same time. The only thing you need to make sure of is that the coolant mixture is the proper ratio and that both radiators are working properly. If not, then there could be some major problems with your engine down the road.

For example, one radiator may overheat while the other does not. This could cause leeching from the non-working radiator which could cause rust and leaks in your engine. So make sure both systems are working properly before mixing coolants.

Key Parts of a Car’s Cooling System

The Thermostat and Thermostat Housing

At the heart of the car’s cooling system is the thermostat. The responsibility of the thermostat is to regulate the temperature of coolant by opening and closing a passage between the engine and the radiator. As it opens, more coolant flows through the system; as it closes, less coolant flows through. This process continues until an equilibrium temperature is reached. The thermostat is located inside a thermostat housing, which can be either integrated or standalone.

Standalone thermostat housings are usually found on cars with front- or rear-wheel drive. They are mounted in the engine bay and consist of a metal housing, thermostat, coolant passage(s) and a coolant outlet pipe (which is usually connected to the radiator). Integrated thermostats are used on most V6 and some V8 engines which use a single head for both cooling and lubrication.

The integrated system uses an internal bypass system that incorporates the coolant passages into the cylinder blooming. This allows for better lubrication and also gives the engine more power by using both heads for cooling instead of one.

To replace a thermostat, you need to remove the housing from the engine block. On front-wheel drive cars, this can be done by removing two bolts on either side. Rear-wheel drive cars may require additional tools such as a special socket set called a “crank pulley” which is used to unscrew the bolts holding the housing in place. You can also get a thermostat housing replacement and change both the thermostat and the housing to ensure no leaks occur in the foreseeable future.

Once it’s removed, you can then unscrew the thermostat and replace it with an identical one. Do the same with the housing and thermostat housing replacement. Make sure that there is no coolant left over from when you disconnected the housing as this could cause corrosion of your engine block.

Cooling Radiators and Radiator Caps

Next up we have radiators. Radiators are an essential part of a car’s cooling system because they dissipate heat away from the engine through a series of fins and tubes. These coolant passages are usually filled with air which helps reduce heat loss, but sometimes they can be filled with oil to further reduce heat loss.

Oil-to-air radiators may seem like the best way to go because it allows you to get both cooling and lubrication in one unit. However, there are some disadvantages such as increased noise due to fan motors and increased weight. Oil can also leak out if not sealed properly. For this reason, most car makers prefer to use air-to-water radiators which are quieter and lighter.

To replace a radiator, you need to first remove any accessories like fan shrouds or fans. Next, disconnect the upper and lower hoses from both ends of the radiator as well as the overflow tank hose if applicable. After that, remove all of the bolts holding down the radiator in place and carefully pull it out from under the car. You can then unscrew the old one and replace it with an identical one.

Make sure that there is no coolant left over from when you disconnected the hose as this could cause corrosion of your engine block.

The radiator cap is used to maintain the pressure of coolant inside the cooling system as well as prevent leaking. It may also have a fan attached to it which helps circulate coolant through the system.

Oil Coolers

Next up we have oil coolers which are usually used on high-performance cars in order to increase cooling efficiency and prevent overheating at high RPMs or during extended hot driving conditions. To accomplish this, the oil cooler has a fan mounted on top of it which blows air through the system and into the radiator. Oi coolers are usually integrated with other parts of the car’s cooling system such as the radiator or fan shrouds.

The main difference between oil and water-cooled engines is that oil coolers do not have internal leaks like water-to-oil radiators because the coolant does not contact the engine block. However, if there is a leak in one of these systems then you will end up with an oily mess underneath your car! Make sure to check all connections for leaks before driving again.

The Final Word

In conclusion, there are many different types of cooling systems in cars today because they all have unique designs. Some use water-cooled engines while others use oil-cooled or even both. However, both types of coolants are used in cars because they each have their own advantages and disadvantages.