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What Is a Radiator?

Educational  ·  May 20, 2019

What Is a Radiator?

What is a radiator and how does it work?

A radiator is a container filled with water, functioning as a heat-exchanging mechanism for cooling the interior heat of an engine and transferring thermal energy from one energy phase to another to ensure that the heat gets cooled. 

They are used in electronics, buildings, and automobiles. Aside from automobiles, some other machines that use radiator for the cooling of their engine are motorcycles, railway locomotives, and stationary generating plants.

Generally, there are two types of cooling systems used in automobiles. We have the air-cooled and the liquid-cooled systems. Air-cooled engines can be found in older vehicles like some Volkswagen and Mercedes. In recent times, automobile manufactures have stopped using this type because it has not been as effective as the liquid-cooling system, but it remains to be used in modern motorcycles.

Components of a cooling system

The radiator is just one aspect of a cooling system, though one of the most important, with the following comprising the rest of the parts:

  1. Hoses
  2. Freeze plugs
  3. The radiator
  4. Water pump
  5. Radiator cooling fan
  6. Thermostat
  7. Heater core
  8. Bypass system
  9. Intake manifold gasket and head gasket

Each of these parts have their own role to play in ensuring that the cooling system is complete, and its function is carried out effectively. They carry out their respective duties collectively, a default in one can render the rest of the components useless.

How does it work?

As earlier discussed, the radiator is a device made for the purpose of regulating the temperature of an engine or machine. The engine generates heat from mechanical friction and the fuel burning process, in order to make your car or machine work well. This generated heat has to be redirected away from the environment of the engine to avoid damage. This is the reason why engines are created to have an in-built, self-induced cooling mechanism.

This cooling system usually includes an exhaust portal through which the heat can be diverted. A part of the cooling mechanism is the oil that lubricates the engine to reduce the extent to which friction will have an effect on the engine. The radiator is another part of the cooling mechanism that kicks at a certain temperature.

When the temperature of the engine becomes too much to maintain proper running of the engine, the thermostat in cooling system detects it. Instantly, this activates the release of water and coolant from the radiator. This liquid moves through pumps to reduce heat. After that the liquid goes through the surface area, it is then sent back into the radiator via the radiator hose.

Aside from the radiator, the cooling system also contains a fan that rotates constantly. near the radiator and opposite the engine. It helps the radiator in the cooling process. External air is also transported through vents, thereby augmenting the cooling process.

Major functions of a radiator 

The radiator ensures that your car runs at an optimal temperature to prevent the engine from getting damaged. Once the engine gets overheated, its internal components like the piston and the cylinder can start to melt. The fuel combustion process is such that it needs the engine to get hot, but not too hot.

The more the engine runs, the quicker the fuel gets converted into vapor in the combustion mechanism, and the more effective the combustion process is. When a radiator works perfectly, it implies that the lubrication of the engine is functioning at full capacity and its parts will be able to turn freely and smoothly, thereby making the engine last longer. 

Summing up, a perfectly-functioning radiator prevents engine overheating, aids engine lubrication, reduces exhaust emission, and improves the performance of the whole cooling system installed in a vehicle or machine. 

Symptoms of a failing radiator 

Watch out for the following symptoms if you suspect that your radiator is about to develop a fault:

1. Dash board warning light: if your dashboard indicators are working fine, the first symptom that will tell you about a faulty radiator are the warning lights. The light comes up to inform you that the engine temperature is getting unbearable for the engine parts. It's a signal that the cooling system is not functioning effectively.

2. Engine overheat: if your vehicle is constantly giving a signal of engine overheat after a short journey (not more than 25 km), it's a sign that the radiator is starting to fail or already damaged. Such issue should be addressed immediately in order to avoid further damages to the engine.  

3. Coolant leakage to the floor: the coolant is the fluid that flows through the radiator and is responsible for relaxing the high temperature generated by the engine. As the coolant escapes from the radiator, the cooling system will start to fail. A mechanic can confirm this by running random pressure test. If confirmed, you will need to replace the radiator before incurring more damage to your engine.

4. Coolant contamination: when getting a coolant, ensure to get one from a trusted and tested supplier. The coolant you use for your vehicle should be normally green, yellow or red. When the radiator starts getting bad, the coolant may become contaminated and become rusty or greasy, preventing the free flow of the fluid. This is usually formed in the radiator of vehicles with a transmission cooler. When the professional who fixes your car comes across this, it is essential that you fix or replace the radiator.

5. Rapid fuel usage: when the temperature of your engine is very high, fuel combustion tends to increase due to heat generated. As fuel burns rapidly, emission from the exhaust also increases. 

You might also experience an automatic engine cut-off if you are using a modern car. This is a feature that is developed to prevent total break-down. It is designed to switch off the engine whenever the temperature gets too much and disable the engine from starting until the high temperature reduces. 

Major parts that go bad after the radiator goes bad

The cooling system is a composition of many parts. So when one part fails to work properly, it generates a ripple effect on the other parts of the cooling system. The major parts that cease to work after the radiator develops a fault are the following:

1. Water pump: When the radiator fails to cool the liquid before it goes into the impeller, the plastic parts of the water pump could melt. It ends up damaging the part of the centrifugal pump and then distort the rate at which the coolant is being transported. Sludge created from contaminated coolant could also cause damage to the water pump.

2. Thermostat: this is the part that is responsible for controlling the temperature and indicating when specific parts of the cooling system kicks in. Different engines operate at different rates of temperature, depending on their size and the components they carry. The thermostat is laid beneath the radiator hose and from there it regulates the temperature of water flowing through the cooling system. When the temperature gets to the optimal point, the thermostat activates specific parts of the system.

When the radiator fails, the fluid becomes too hot, which usually causes the thermostat to get damaged. The thermostat stops working immediately, the valve in the thermostat remains closed, which makes your engine start to overheat.

3. Heater core: this is a part that looks so much like a radiator but smaller. It also contains a network of gauge tubing that works effectively in the production of hot air for the heat system. If sludge from the radiator gets in to the heater core, it blocks the small gauge tubing of the heater core. Also, when the radiator fails and the engine overheats, the tube connections in the heater core may start to break. So ensure that you pay careful attention to the signs on your dashboard or indicator box.

Maintenance tips to avoid breakdown in the cooling system

Failures in the cooling system are typically associated with bad maintenance practices and carelessness. They may lead to engine breakdown; thus, prevention is important. Observing the following precautions can do a lot:

  1. Immediately replace any malfunctioning part of the cooling system.
  2. Regularly check the coolant level.
  3. Consistently inspect the radiator for leaks.
  4. Replace conventional coolants every two years or 48,000 km, or extended life coolants at every five years or 240,000 km.
  5. Regularly check belts and hoses to see whether they are worn-out and need replacement.
  6. Inspect the concentration and condition of the coolant.

There are some tests that should be conducted regularly to ensure that the cooling system works properly. Some of them are:

  1. Thermostat test - to ensure proper opening and closing of the valve
  2. Pressure test - to check for external leakages
  3. Radiator pressure cap test - to maintain an optimal pressure within the cooling system
  4. Internal leak test - to identify if gasket is blown
  5. Engine fan test

Generally, the common cause of overheating and engine shutdown due to cooling system failure is coolant leakage. 

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