What is an Oil Cooler? | How does an Oil Cooler work?

What is Oil Cooler?

An oil cooler is a part of the vehicle that uses to eliminate additional heat of the engine through a heat exchanger. The engine cooler uses oil to cool the mechanical parts of the engine.

oil cooler

In contrast to the water-based cooling system, the oil cooler is designed as a small radiator. The main function of the oil cooler is to reduce the vehicle engine temperature while driving. It only works during the operation of the vehicle.

The cooled oils have many uses as heavy-duty transmission oils. An engine with a cooling fan has the ability to quickly cool the oil-based and water-based radiators.

Due to the oil cooler’s role as an extra cooling device, the high temperatures of the engine significantly reduce when it is applied to an air-cooled engine. Due to the oil coolers, the service life of the engine significantly extends. Heavy trucks take full advantage of the oil cooler and help put more pressure on the drivetrain.

Improved cooling allows heated engine oil to run effectively at lower temperatures, reducing the chance of early failure. The degradation of oil loose reduces the functionality of the engine oil; due to that, it doesn’t properly cool and lubricate the engine.

Types of Engine Oil Cooler

The engine oil coolers have the following major types:

  1. Oil-to-water cooler
  2. Oil-to-air cooler

1) Oil-to-water cooler

In this oil cooler, the refrigerant flows through the heat exchanger elements of a specific component. The refrigerant activates by extracting heat from overheated oil or adding heat to cold oil.

2) Oil-to-air cooler

This is a small cooler that cools the engine oil directly from the air surrounding the cooling fan. These coolers most commonly use a thermostatically controlled bypass valve to prevent engine oil from flowing through the cooler until it has reached up to a specific working temperature.

Working Principle of Oil Cooler

The engine oil cooler is one of the most important parts of the engine. The main function of the engine oil cooler is to properly cool the engine oil and the engine parts.

The oil-to-air cooler installs in the radiator front. The oil coolers work during the operation of the vehicle. When the vehicle runs, the oil cooler activates. As a result, the engine oil quickly gets the coolest fresh air from the cooling fans. In maximum systems, the oil leaves the engine in the form of a “sandwich” adapter.

The adapter installs between the engine block and oil filter to allow hot oil to pass through the oil filters. As the hot oil passes through the filter, then it flows by the oil cooler before flowing back to the engine to repeat the process. Some adapters have a thermostatic regulator that stops the flow of oil until a certain temperature is reached.

Few vehicle cooling systems have a remote control that forms the base of the oil filter and an extra adapter that contains the existing oil filters. The existing oil filter connects to the plumbing hose that connects the remote filter base to the radiator.

For vehicles that do not have enough space in the radiator front, the manufacturer provides radiators on other parts of the engine. Some have their own cooling fans.

Symptoms of a Bad or Failing Oil Cooler

As the engine oil cooler goes bad, it produces one of the below-given signs:

  1. Leakage of the oil cooler adapter
  2. Oil in the cooling system
  3. Engine Coolant Leak from the oil cooler
  4. Engine Overheating
  5. Coolant in the Oil
  6. Bad Thermostat
  7. Reduced Engine Performance
  8. Higher temperature on the Temperature Gauge

1) Leakage of the oil cooler adapter

The oil leakage from the adapter is one of the most common signs of a bad engine oil cooler.

The system has two oil cooler adapters:

  1. One adapter links the cooler to the oil lines
  2. The second adapter transfers the cooled oil back to the oil sump.

As the adapter goes bad, it may lead to oil leakage from the engine. If the oil leakage is very low, you may observe an oil puddle at the engine bottom. You may also notice the oil leakage on the ground behind the vehicle.

If you notice an oil leak under the engine, you must immediately contact a professional mechanic. If you ignore the oil leakage, then it may lead to engine overheating. Therefore, you must take the leakage failure seriously as the entire engine has lost enough lubrication. This problem can lead to increased engine temperatures and premature component wear.

Read More: Signs of Oil Leakage

2) Oil in the cooling system

When the oil cooler adapter leaks internally, the engine oil starts going into the cooling system.

When the adapter is damaged internally, the oil pressure becomes higher than the internal pressure of the cooling system during the engine operation. Due to the pressure difference, oil is pushed into the cooling system. Ultimately, this may quickly reduce the oil level and cause severe engine damage.

3) Engine Coolant Leak from the oil cooler

The coolant leakage problem is similar to the first fault. If you do not fix this problem one time, whether the leak is small or large, it may lead to the engine.

4) Engine Overheating

The engine overheating is one of the major symptoms of a bad engine oil cooler. As we discussed, the cooler prevents the engine from overheating. When the cooler fails, it doesn’t properly cool the engine oil, which leads to engine overheating.

5) Coolant in the Oil

The coolant in the engine oil mixes when the engine doesn’t work, but the cooling system is pressurized. In such conditions, the cooling system forces the coolant into the oil sump. Excessive oil levels in the sump may badly damage the engine if the crankshaft hits the oil during its rotation.

6) Bad Thermostat

A faulty thermostat may lead to engine overheating. A thermostat uses to regulate the oil flow to an oil cooler. It acts as a valve that opens at a certain oil temperature.

When the thermostat goes bad, it will stop the oil circulation to the oil cooler and cause engine overheating.

Read More: Sings of Faulty Thermostat

7) Reduced Engine Performance

The reduction in the engine performance is one of the main signs of a bad oil cooler. This is noticeable in slow acceleration and low top speed. The engine also shows high temperatures on the heat gauge during operation. This is because the engine doesn’t cool down fast enough and overheats.

8) Higher temperature on the Temperature Gauge

The temperature gauge shows the engine temperature. It is located on the car dashboard. The higher temperature on the temperature gauge shows that your engine is not cooling properly. The engine may overheat due to different reasons, and a bad oil cooler is one of them.

Advantages and Disadvantages of Oil Cooler

Advantages of Engine Oil Cooler

  1. It helps to cool the hot oil.
  2. It helps to properly cool the engine parts.
  3. The engine oil cooler ensures efficient oil cooling before pumping it throughout the engine.
  4. It prevents the engine from overheating.
  5. It is very easy to install.
  6. It improves the performance of the engine.
  7. Oil circulation is controlled and efficient.
  8. The oil coolers reduce the use of the water-cooling system due to that they prevent the engine parts from corrosion.

Disadvantages of Engine Oil Cooler

  1. It uses oil instead of water. The oil is flammable, which increases the risk of fire.
  2. These systems consume a high amount of oil for efficient operation.
  3. They require regular maintenance for efficient working.
  4. The failure of the engine cooler oil leads to engine overheating.
  5. The engine oil is expansive.

FAQ Section

What are the signs of bad Oil Cooler?

As the engine oil cooler goes bad, it gives one of the below-given signs:

  1. Leakage of the oil cooler adapter
  2. Higher temperature on the temperature gauge
  3. Oil in the cooling system
  4. Reduced engine performance
  5. Engine coolant leak from the oil cooler
  6. Bad thermostat
  7. Coolant in the oil
  8. Engine overheating

What are the types of the oil coolers?

The oil coolers have the following types:

  1. Oil-to-water cooler
  2. Oil-to-air cooler

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