Does Motor Oil Evaporate? Everything You Need to Know!

When it comes to motor oil, many people have questions. They want to know if it evaporates and how long that process actually takes.

The thing is that engine oil is a mixture of petroleum liquids used to lubricate engine parts. It consists of 90% paraffinic (heavy) hydrocarbon base stock and 10% additives.

In this post, we are going to explain everything you need to know about motor oil evaporation so that you can have a better understanding going forward.

When Motor Oil Evaporates?

Does Motor Oil Evaporate

If you own a car, then you likely know that oil in your engine should be changed periodically. Unfortunately, many people neglect checking the oil level on their vehicle which can lead to issues with performance and engine longevity.

There are various reasons why a car’s oil may run low. Some potential causes include an engine leak or evaporation of the oil.

Motor oils typically consist of 90% paraffinic (heavy) hydrocarbon base stock derived from crude oil, with additives added for improved properties. They are then classified into specific grades based on how thick or thin they become at operating temperature (212 degrees Fahrenheit in your engine).

Lubricating internal moving parts and absorbing heat requires oil with a viscosity of at least 1. This determines its resistance to flow, creating a film between parts that helps keep your engine running smoothly.

But when oil is exposed to high temperatures, its lighter molecules become unstable and start to vaporize. As a result, the oil leaves the crankcase and exits as a gas that can be vented out.

This is a common issue that can cause performance issues and decreased mileage. However, it’s not usually an issue when the vehicle isn’t in use. But if your engine is regularly used and exposed to high temperatures, then changing oil more frequently and topping off as necessary is recommended.

Read Also: Does Motor Oil Have Shelf Life

Why Does Motor Oil Evaporate?

It is safe to say that motor oil evaporates at high temperatures and this can lead to major issues with your car. If the oil dries up, it could result in engine damage as well as other complications.

Engine oil becomes thinner when exposed to gaseous state, leaving behind thicker oil. As this dries out, it becomes harder for your engine to maintain proper lubrication.

In some instances, high temperatures can even cause the oil to get burned. This occurs because oil’s volatility rate increases when exposed to extreme temperatures.

The higher the volatility rate of the motor oil, the more likely it is to evaporate when exposed to heat. Evaporation of motor oil can negatively impact your vehicle’s overall performance and drastically reduce mileage and fuel efficiency.

We think the best way to reduce motor oil evaporation is by using low viscosity oil or switching to synthetic oil. Synthetic oil has a lower volatility rate and does not evaporate quickly when exposed to high temperatures, helping you steer clear of many issues associated with engine oil evaporation.

Effects of Motor Oil Evaporation

Motor oil

Evaporation is a commonly observed occurrence in liquids. It’s the gradual disappearance of a liquid when exposed to sufficient heat energy, such as when it reaches its boiling point or receives direct sunlight.

Engine oil is designed to resist evaporation, but can become compromised when exposed to high temperatures for extended periods. Therefore, it’s essential that you check your oil level on a regular and add oil as needed in order to prevent any issues with evaporation.

It’s also essential to check your car for signs of leaks. A leak can cause your oil to evaporate rapidly, leading to a variety of issues such as decreased fuel efficiency and higher emissions.

One thing for sure is that motor oil should be replaced every 2000-3000 miles. If your vehicle’s oil levels appear to have decreased significantly, take it to a mechanic to check for signs of a leak.

As your oil starts to evaporate, it leaves behind a thicker and more viscous version of the original fluid. This makes it difficult to properly lubricate your engine, leading to increased wear-and-tear.

Evaporation not only leaves behind a thicker, less fluid oil, but it can also cause sludge to accumulate in the engine compartment. This increases the time it takes to change your vehicle’s oil, leading to more frequent changes and higher costs which can be a drawback for those on a tight budget.

Learn More: Can Motor Oil Damage Car Paint

How to Stop Motor Oil From Evaporating?

If it’s a case where you’re concerned that your engine’s oil is evaporating too quickly, there are steps you can take to prevent this. One of the best solutions is using oil designed for high heat resistance; this helps ensure the oil lasts longer in service.

You have two choices for preventing evaporation: low viscosity oils designed specifically to resist evaporation, or synthetic oil. Though more costly, synthetic oils have a lower evaporation rate than regular oils which makes them better suited to your engine.

Another way to prevent evaporation is keeping your car’s engine cool. This helps slow the evaporation process and makes it less likely that you’ll run out of oil while on standby.

Maintaining your engine’s temperature can also help reduce oil oxidation, which may lead to sludge building up in its interior. If there’s a lot of sludge present, you may need to change your oil more frequently.

Evaporating oil isn’t usually a concern while your car sits idle on the lot, but it can become an issue if you drive frequently or keep it in warm environments. While oil evaporation rate increases when running or heated, it’s barely perceptible when left parked at home.

How Long Does Motor Oil Take to Evaporate?

Motor oil is a liquid and, like all liquids, it evaporates when exposed to high temperatures.

Motor oil takes some time to evaporate, which is why it doesn’t usually disappear immediately when the engine is turned off. On average, most types of oil dry within five to thirty minutes after being turned off.

No need to worry about running out of engine oil even if you don’t change it frequently – unopened motor oil (both conventional and synthetic blends) typically lasts 2-5 years depending on driving habits.

That is why it is essential to regularly check your engine oil level with a dipstick. If it appears low, evaporation could be occurring and lead to serious issues.

If you’re uncertain whether your oil is evaporating or not, taking it to a mechanic can help. They will also determine whether you need to change the oil or not.

In addition to checking your oil, it’s also important to verify that the PCV valve in your engine is functioning properly. Defectives with this valve may result in an excess supply of oil in your engine and even lead to a burning accident.

If there is an oil leak or spill, it is critical to clean it up promptly. Doing so can prevent having to replace the oil in your engine and protect other parts from being damaged.

Should I Change the Oil When it Starts Evaporating?

Generally, there is no need to fret over evaporation when it comes to motor oil. As long as you change it regularly, there should be no issues with evaporation.

However, if your car is losing oil but there’s no smoke or leakage coming from the engine, it could be time for an oil change. Doing this helps ensure that your car runs optimally and prevents any serious issues down the line.

There are a few things that can cause your motor oil to evaporate, such as hot weather or unfavorable driving habits. If not handled promptly, this could lead to major issues.

Another factor that may cause your oil to evaporate is old, worn-out parts in your engine. This could occur due to damaged valve seals or piston rings which should keep oil from escaping into the combustion chamber; however, when these parts fail, oil may seep past them and into the atmosphere.

If your car is experiencing these kinds of problems, it’s wise to get it in for an oil change as soon as possible so the mechanic can begin fixing them. Doing this could save you a considerable amount of money in the long run.

The type of oil you use will also influence how quickly it evaporates, as some oils are heat resistant. This allows your engine to burn through oil more quickly, leading to reduced evaporation time.