Oil Cooled Engine: Working, Advantages & Disadvantages

In this post, we will going to learn what is oil cooled engine and how it works. This article will also go over the working, advantages, and uses.

What is a Oil Cooled Engine?

Oil cooled engine refers to the use of engine oil as a coolant, often to remove excess heat from an internal combustion engine.

A hot engine transfers heat to the oil, which typically passes through a heat exchanger called an oil cooler, which is a type of radiator. The cooled oil continually flows back into the hot object, cooling it.

Oil Cooling Engine

The oil-cooled engine has the same cooling fins as the air-cooled engine, but there is a small oil-cooler mounted externally. This helps cool the engine oil passing through passing air.

The hot engine oil passes through this radiator, which cools it with air before pumping it back into the engine. Compared to air-cooled motors, oil-cooled engines are more effective at cooling running components because cooler oil passes through them.

Read Also: Different Types of Engines and Their Working

Working of Oil Cooled Engine

The purpose of oil cooling is to regulate engine temperature. In addition to the use of air cooling, this approach employs an oil cooler to lower the temperature of the engine oil.

As the engine runs, the oil circulated within it absorbs the heat generated inside, and beyond a certain temperature level it begins to lose its viscosity. The engine temperature starts to rise as the lubricant’s density drops because of an increase in internal component friction.

This is prevented by having the engine oil circulated between “oil coolers,” which ensures that it stays at the ideal operating temperature.

This system also uses outside air to cool the engine oil as it travels through an externally mounted oil cooler that resembles a radiator. In addition to being used for lubrication, this oil is also used as a liquid coolant in the cylinder head.

For oil cooling, more oil capacity and a higher oil pump flow rate are needed than in an oil system that is only used for lubrication.

Read Also: How does a 4-stroke engine works?

Purpose of Oil Cooling

It is ideal for engines where air cooling is adequate for most of the running time, but extra cooling is needed for a specific performance range, in which it is vital that the oil maintains its viscosity and minimizes friction.

However, cooling only gets better at higher speeds because atmospheric passing air is still the primary component used.

High-performance engines that generate massive amounts of heat under all operating situations cannot be equipped with oil cooling since it is less effective than liquid cooling.

Advantages of Oil Cooling

  1. Oil can be used to cool objects that are 100 °C or greater because it has a higher boiling point than water. However, pressurized water cooling can reach temperatures above 100 °C.
  2. Since oil is an electrical insulator, it can be utilized within transformers or in direct contact with electrical devices.
  3. No additional coolant tanks, pumps, or radiators are needed because oil serves as a lubricant already. However, all of these components might need to be larger than they would be otherwise.
  4. In contrast to cooling water, which can corrode the engine, oil prevents corrosion naturally.
  5. As a consequence, if a gasket fails and coolant oil enters the combustion chamber or sump, it would be an inconvenience; but if water leaks, then substantial engine damage might result.

Disadvantages of Oil Cooling

  1. Coolant oil should only be used to cool items that are between 200 and 300°C; otherwise, the oil can decompose and might leave ashy debris behind.
  2. Pure water can boil or evaporate, but it cannot decompose, however it can get contaminated and become acidic.
  3. If coolant needs to be added to the system, water is usually accessible, but oil could not be.
  4. As opposed to water, oil might catch fire.
  5. Water may absorb more engine heat than oil because of its specific heat, which is about twice that of oil.
  6. For high-performance or racing engines, water may be the best coolant if the engine is continuously creating a lot of heat.

Read Also: What is 2-stroke engine?

Application of Oil Cooled Engine

Oil Cooled Engine

Oil cooling is widely utilized to cool high-performance motorcycle engines that do not employ liquid cooling. In a typical motorcycle setup, the cylinder head receives extra cooling while the cylinder barrel is left air-cooled.

The lubricating oil circulation system is already in place, therefore this oil is pumped to the cylinder head where it serves as a liquid coolant. When compared with a solely lubrication oil system, oil cooling requires more oil capacity, higher pump flow rates, and a larger oil cooler.

Suzuki first employed the “SACS” oil-cooling system on their GSX-R sportbikes in the 1980s, but they eventually moved to water cooling.

The Wankel engine uses both liquid and oil cooling to effectively control its excessive heat. This rotary engine is most known for its use in the Mazda RX-7 and RX-8.

Lubrication is a basic method of oil cooling. Some slow-turning early engines featured a “splashing spoon” beneath the connecting rod’s big end. This spoon was intended to cool and lubricate the underside of the piston by dipping into sump oil and splattering oil around.

Advantages of Oil Cooled Engine

Following are the advantages of using oil cooled engine:

  1. Oil-cooled systems are significantly more efficient than air-cooled ones.
  2. Engines that run on oil have simple technology.
  3. Compared to liquid-cooled engines, it is less expensive and much simpler to maintain.

Disadvantages of Oil Cooled Engine

Following are the disadvantages of using oil cooled engine:

  1. For high-performance bikes, this kind of cooling system is likewise inappropriate.
  2. They are still not as efficient as motorcycles with liquid-cooled engines, despite being superior to those with air-cooled engines.

Conclusion

When the benefits and drawbacks are considered, it is clear that an oil-cooled engine is superior to an air-cooled one. Still, it might not be the ideal option for people who enjoy taking lengthy bike rides.

That’s it. Thanks for reading. I hope I have covered everything. It would be helpful if you could let me know if there was anything I missed or if you have any doubts about anything I wrote.

Resources or External Links:

  1. https://en.wikipedia.org/wiki/Oil_cooling

FAQs

How does an oil-cooled engine work?

The process of using motor oil as a coolant, usually to remove excess heat from an internal combustion engine, is known as oil cooling. Heat is transferred from the hot engine to the oil, which is then normally sent through a heat-exchanger, which is commonly an oil cooler, a kind of radiator.

Is an oil-cooled engine good?

An oil cooler is an ideal method for engines where air-cooling is sufficient for much of the time, but where additional cooling is needed to maintain viscosity and reduce friction during certain performance ranges.

What is the purpose of oil cooling?

An oil cooler keeps the oil supply at the ideal temperature all the time. It is a smaller, independent radiator from the engine’s primary radiator. Its function is to increase the lifespan of the engine and the transmission by cooling the oil that is going through the coils.

What is the difference between a liquid-cooled engine and an oil-cooled engine?

The oil cooler cools the engine oil as it passes through it. Engines such as the Apache 200 and Pulser 220 are oil-cooled. In liquid-cooled engines, liquid coolant is utilized to keep the engine cool. The coolant contains anti-freeze qualities.

Which is good, oil-cooled or air-cooled?

The main benefit of oil-cooled engines versus air-cooled motors is the cooler oil that is transported through the engine, which cools the internal moving parts.