Why engine oil leak from car?

An engine oil leak is often a symptom of damage that needs to be repaired quickly. How urgent the repair is depends largely on the location and severity of the leak and the overall condition of the car. Sometimes the cavity can be significant, putting you at risk of a serious breakdown. Find out what causes an oil leak and how to fix it


Can an oil leak damage my engine?

Oil leakage from the engine creates the risk that the unit will start to run out of lubricant. This is especially true for modern engines, which are equipped with small capacity oil pans. This can quickly lead to serious and often irreversible damage to components such as pistons, pan, valves, timing belt or chain, variable camshafts, and turbochargers.

The above list already looks expensive at first glance. Repair and replacement of these components will run into the thousands rather than hundreds of dollars. So it doesn't matter whether there is an oil leak on the right side of the engine or the left - each needs to be addressed and quickly fixed.


What causes engine oil leak?

Where does an engine oil leak come from? There are many causes of leaking oil. Sometimes it's a mechanical failure, a material defect, or improper installation. Perhaps it's too much oil pressure in the engine or the wear of rubber and silicone seals - and this scenario can be real. The operating conditions for oil and rubber components are extremely harsh, dealing with powerful temperatures and high pressure.

Keep in mind that an oil leak can also happen in a new car. In such a situation (as long as it is not the result of mechanical damage or improper operation), it is more likely the result of a material defect or improper installation.

Oil leakage from the engine can also be the result of too high oil pressure in the lubrication system or other serious engine defects. However, they are much more common in older sold vehicles with above-average mileage. In this case, not only is the engine already heavily worn out, but the rubber and silicone seals or hoses and lines begin to lose their original properties.

Sometimes the sweating of the engine and the passage of lubricant through the seals are not the result of your negligence. It is simply a matter of natural wear and tear of the seals, which have a certain life cycle. Once it is exhausted, it is subject to malfunction, and the need for a replacement arises. The same principle applies to other operating parts, including suspension or chassis components.


What makes engine oil leak?

Remember that the oil running in the engine is subjected to extreme stress. After starting, it heats up to a very high temperature and circulates through the lubrication system under pressure. For example, a turbocharger can heat up to 1,000 degrees Celsius - and it too is lubricated and cooled by oil. Extreme conditions mean that the lubricant must do its job in both very high and very low temperatures, to which engines are exposed by freezing temperatures.

Almost as difficult conditions must be faced by gaskets, located at the connection points of sensitive vehicle components. They are the most common weak points where leaks occur. After years of operating in high-temperature conditions, they can become damaged. This is the result of natural wear and tear, not a matter of mistakes made by the manufacturer.

In addition, you need to know that while gaskets can handle heat, they can't handle high temperatures. Therefore, beware of overheating the engine. Even a single spike in the heat of the drive unit can make the gasket does not withstand it. The result will be an oil leak from the diesel or gasoline engine - only that it will leak directly into the cooling system. The oil will mix with the fluid, and you will see a raging temperature gauge and feel a marked decline in power. That's where the characteristic residue under the cap in the coolant reservoir will come from.


How to check engine oil leak?

To check the engine oil leak, just look under the hood. Pull out the dipstick and check the oil level. If there is too little of it, look at the engine compartment. You may notice oily stains on the lower engine cover. This is an obvious sign of a leak. Is it a good idea to only watch the oil light on the dashboard? Not really. The oil light often reacts when there is not enough lubricant for the vehicle to run properly. This means a serious risk of seizure of the mechanism or serious damage to the attachment.

There was an unexpected and sudden oil leak from the engine. This is often the result of mechanical damage. It may mean that you have punctured the oil pan after driving over an obstacle. No oil in the engine? Don't start the car right away. Otherwise, you will seize the engine in a few minutes. In addition, you may find that the oil is running out, but you can't see that the engine is sweating. Such a scenario, unfortunately, is even less optimistic. This is because the leak is still there, but it is seemingly invisible on first verification.

In a situation in which the engine oil leak is there, but you can't see it, the indication may be one thing - the seals in the combustion chamber have been damaged. As a result, the lubricant is burned together with the fuel-air mixture. This can be caused by leaks inside the turbocharger. In this case, you should notice bluish exhaust gas appearing from the exhaust pipe.


How to fix engine oil leak?

Older engines are often heavily soiled. Dust and water collect in the chamber despite being shielded by a hood and plastic grille. This makes it much more difficult to observe emerging oil leaks. If there are difficulties locating leaks, it is worth washing the engine and only then observing where the leak is coming from. 

When replacing gaskets, it is best to opt for the highest quality parts, as any savings on parts or service will quickly pay off in the form of a shortened service life. Sometimes the first symptoms will appear as soon as you pass the service gate - all it takes is one point where the mechanic improperly tightens the drain plug in the sump.

You should keep in mind that the inspection of oil leaks and further repair should be done by a qualified workshop. Especially since lubrication issues are essential for any car and can determine the appearance of an expensive to fix defect. Therefore, a car with an oil leak should go to a professional auto repair shop as soon as possible. 

Read also:


How to avoid oil engine leaks?

The condition of engine seals is of great importance when it comes to oil leaks. Special attention should be paid to their condition and age. The conditions surrounding the gaskets are harsh. Try to ensure that there are no further problematic stresses that will project their strength. It is advisable to avoid high revs on a cold engine and not to keep the highest revs for a long time. It is unhealthy for the car to ignore the controls and forget to check the level or to change the oil regularly. It is also not worth saving on parts or gaskets. The way the engine is operated makes a big difference in the life of the gaskets and, as a result, in maintaining tightness and avoiding leaks. 

Note that underestimating lubrication system infirmities can be very costly, so it's better not to underestimate the lights that come on, the messages displayed, or the decreasing amount of oil in the system. 

Photo by Freepik