How to Stop an Oil Leak in a Car

by Synthetic Oil | Last Updated: April 23, 2023

You walk out in the morning to begin your commute to work and you notice something under your car. Is that oil? No, it can’t be! The sight of leaking oil is bound to make your heart drop, because you assume that it is going to require the aid of a mechanic to fix. Although oil leaks are a big deal and need to be repaired, you do not need to be an automotive tech to learn how to stop an oil leak. There are DIY options that can be accomplished right in your driveway.

Here is everything you need to know to effectively stop an engine oil leak.

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What Causes an Oil Leak?

Learning how to stop an oil leak begins with knowing where those leaks may come from. After all, there is no point in fixing something only to miss the actual cause and have it happen again. That’s a waste of your time and energy, and you don’t have to deal with that. So, here are some common causes of oil leaks to consider:

• Worn or damaged gaskets: Gaskets are used to create a seal between different parts of the engine. Over time, these gaskets can become worn or damaged, causing oil to leak out.
• Faulty seals: Seals are used to keep oil from leaking out of the engine. If these seals become worn or damaged, oil can leak out.
• Loose or damaged oil pan: The oil pan is located at the bottom of the engine and holds the engine oil. If the oil pan becomes loose or damaged, oil can leak out.
• Cracked engine block or cylinder head: If the engine block or cylinder head develops a crack, oil can leak out.
• Improperly tightened or installed oil filter: If the oil filter is not tightened properly or is installed incorrectly, oil can leak out.
• Overfilled oil: If too much oil is added to the engine, it can cause the oil to leak out.
• Extreme temperatures: Extreme heat or cold can cause seals and gaskets to become brittle and crack, leading to oil leaks.
• Corrosion: Corrosion can cause damage to the engine components, including seals and gaskets, leading to oil leaks.

You may be able to inspect these things on your own at home. However, if you are uncomfortable with seeking out the cause of the oil leak, it is highly recommended that you have the vehicle inspected by a professional. They will be able to diagnose what is going on.

How to Stop an Oil Leak in Your Vehicle

Now it is time to figure out what is causing the leak and how to fix it. If you have not already, open the engine bay and investigate. It may be best to crawl under your vehicle and start inspecting the common places oil leaks form. You may need a jack to lift your car up high enough to see everything clearly. Before you lift your car and jump underneath please ensure you know how to do this safely. Other recommended tools include jack stands, replacement pairs (if necessary), and a torque wrench. Shine some light around the underside of the vehicle, looking for any stains or speckles of oil. Depending on the severity of the leak, you may even find rivulets of oil coming from the crack or have it drip on your clothing.

Even if you do not find a cause immediately, it is best to proceed using the following steps:

Tighten Loose Connections

While doing your inspection, you may come across a loose connection, such as a loose oil drain plug or an improperly installed oil filter. Fixing oil leaks caused by loose connections is easy: Tighten them. That should stop the leak. If it doesn’t, then you may have a bigger issue on your hands.

Replace Damaged Gaskets and Seals

Gaskets and seals are essential components in an engine that help to create a seal between two surfaces, preventing oil or other fluids from leaking out. When these gaskets or seals become damaged, they can no longer create a proper seal, which can lead to oil leaks.

Gaskets and seals are prone to cracking and breaking when they grow brittle, which opens up gaps in the seal that allows engine oil to seep out. General wear and tear, improper installation, and over-tightening can lead to gaskets and seals failing. Furthermore, if you had any chemical spillage, such as transmission fluid or coolant splashing onto the gaskets or seals, it could eat through the materials, weakening the connection.

One of the best ways to fix a leak caused by damaged gaskets and seals is to replace them. Keep in mind that some gaskets and seals are easier to access than others. If you are not comfortable with replacing certain gaskets and seals, be sure to take your vehicle to a mechanic.

Try Some Oil Stop Leak Products

If you are not entirely sure about where the leak is coming from, you can try an additive specially designed to stop engine oil leaks, such as ATP Automotive reseal, Bar’s Leaks Oil Stop Leak, and BlueDevil Oil Stop Leak. These products work by swelling or softening the rubber seals and gaskets in your car’s engine, which can create a fuller seal and reduce or eliminate any oil leakage.

Typically, oil-stop leak additives are made from a combination of petroleum distillates, polymers, and esters. You can add them directly to the engine oil, as they are compatible with most types.

Here are some things to keep in mind if you plan on using an oil stop leak:

• Follow the instructions carefully. Oil-stop leak products typically come with instructions that should be followed carefully to ensure proper use. It’s important to use the correct amount of product for your engine size and to add it to the engine oil as directed.
• Don’t overuse the additive. Using too much oil stop leak product can actually make the problem worse by clogging oil passages and reducing oil flow.
• Be patient. Oil-stop leak products may take some time to work, so it’s important to be patient. It may take several days or even weeks for the product to fully take effect and stop the oil leak.

Change Your Oil

If your engine oil is thin and worn, it may be more prone to leaking. To explain: Old and dirty engine oil itself is not likely to cause oil leaks, but it can contribute to the deterioration of engine gaskets and seals which can lead to oil leaks. Over time, engine oil can become contaminated with dirt, debris, and other contaminants that can cause it to break down and lose its lubricating properties. This can cause increased friction and wear on engine components, including gaskets and seals, which can eventually lead to leaks.

Furthermore, old, sludgy engine oil may clog up passages within the engine and restrict the flow of oil. In turn, the pressure inside the engine is elevated, which may lead to gaskets and seals failing.

It’s important to change your oil regularly, as this will not only maintain performance but also extend the overall life of the engine and all its parts. Adding a thicker, slightly more viscous oil can help to reduce the leak by creating a better seal. However, it’s important to use an oil that is compatible with your engine and follow the manufacturer’s recommendations. During this oil change, you may also want to repair or replace the oil pan. Don’t forget to install a brand-new oil filter, as well!

Have Any Damaged Engine Pieces Repaired or Replaced

Cracked engine blocks and cylinder heads can be a cause of engine oil leaks, but, fortunately, they are not as common as other causes such as damaged gaskets or seals. Cracks in the engine block or cylinder head can allow oil to leak out of the engine, which can lead to a range of problems including decreased engine performance, increased oil consumption, and potentially catastrophic engine failure if left unchecked.

The most common causes of engine oil leaks are typically related to damaged gaskets or seals, as we discussed earlier. However, engine blocks and cylinder heads can develop cracks due to a variety of factors, including:

• Overheating: Excessive heat can cause engine components to warp or crack, including the engine block and cylinder head.
• Freezing: When the coolant in the engine freezes, it expands and can cause cracks in the engine block or cylinder head.
• Wear and tear: Over time, engine components can become worn and brittle, which can make them more prone to cracking.
• Manufacturing defects: In some cases, engine blocks or cylinder heads may have manufacturing defects that can lead to cracks. Check for any recalls or take your vehicle to the dealership where you purchased it.

Unfortunately, these problems are not easily solved at home. You may need to employ a professional for assistance.

Take Your Vehicle Out for a Test Drive

Do you believe that the problem is solved? Then it is time to take your vehicle for a spin. Before that, though, be sure to check the oil level and top off the level. Once you do that, turn the vehicle on. Do not close the hood yet. Instead, watch the engine while your car runs. Look at the pieces you may have adjusted or replaced. For example, you may notice that oil bubbles up around a new gasket or that there is burning oil and smoke.

If nothing happens, wait about 5 minutes before moving your car several feet away from its original position. Check for any fresh oil spots on the driveway. Any puddling or drops mean that you have to repeat the inspection and repair process. Just remember to let your engine cool before working with the pieces and oil.

Once everything checks out, be sure to take your car for a drive around the block for any symptoms or other issues.

Final Thoughts on Stopping Engine Oil Leaks

Now that you know exactly how to stop an oil leak in your vehicle, be sure to apply this information. Although no one wants to deal with leaking engine oil, understanding the reasons for the occurrence can make it much less of a headache. Knowing how to stop an oil leak is definitely great information to have, particularly when you want to save some money on costly repairs or replacements.