Oil Cap Stuck – How to Remove It?

Do you have to use force to open the oil cap of your engine? Perhaps you have not been checking your oil level these past months. In this article, I’ll discuss the oil cap stuck issue – how to remove it?

If you can’t remove the oil cap, wait a few minutes until it gets cold. Then put some oil on the edge of the lid so it will loosen its grip on the oil fill port. After removing the oil cap, clean its rubber seal and then put clean lubricating oil on it to prevent it from getting stuck again.

Likely, you can’t remove the oil cap because you haven’t checked your engine oil regularly. If you don’t check it often, there will be a buildup of burnt oil on its outer edges. The accumulation of solidified oil on the cap will get thicker and harder over time. That’s the reason why it’s more challenging to remove it.

Read on to learn more about removing a stuck oil cap, why it got stuck, and how to prevent it from getting stuck again.

Oil Cap Stuck

Oil Cap Stuck

If you can’t remove your oil cap from the engine after driving your car, wait a few minutes until the engine and the cap cool down. Then put some lubricating oil on the outer edges of the lid so it will lose its grip on the engine oil port.

With a clean rag, twist the cap and see if it moves. Then using light force, press your palm on the cap and give it a little twist, and the cap will give way. Now, you can remove it from the oil port.

Before locking up the oil cap on the port, pour some lubricating oil on its rubber seals. This will prevent the cap from getting stuck again, even if you’ve not been checking on your engine oil regularly.

That’s probably the thing that caused the oil cap to get stuck. You have not been changing your motor oil regularly. If you don’t do this, one of the consequences is the solidified oil buildup on the oil cap, especially in its inner parts.

That’s already a tip to avoid this problem: check your engine oil and change it regularly. It’s not only for your engine but for your oil cap as well.

How Do You Open a Stuck Oil Cap?

It is not difficult to remove a stuck oil cap. You can use several tools if you can’t remove them by hand. They are all available in the market. You can use an oil cap remover, Channel lock pliers, a strap wrench, or a Vice grip to loosen its grip on the oil port.

Lubricating oil sprayed or applied directly on the cap’s inner edges will also make it easier to unstick the cap from the engine oil port. To tidy up your work, use a clean rag to wipe the oil that could splatter on the area.

One thing you should not do when removing a stuck oil cap is not to use excessive force. You can damage the oil cap or even the engine oil port if you do that. Only use enough force to get it out of its stuck position.

If you have your car manual, you will have specific instructions to remove your car’s oil cap properly. I’m unsure if it contains instructions for removing the oil cap if it is stuck. Anyway, here are some common ways car mechanics do it:

1. Cool Down the Engine

If you are trying to unstick the oil cap after you’ve just driven your car, allow it to cool down for a few minutes or be just warm enough to work on the oil cap.

2. Use a Clean Cloth

Get a clean cloth and cover the oil cap with it. This rag will help the cap remover or whatever tool you have on hand to gain a grip on the cap.

3. Use the Cap Remover

Now, put the cap remover over the clean cloth. Make sure that the cap remover is holding the cloth securely. Then twist it with just enough force. If you do it right, the oil cap will give way.

4. Lubricate the Outer Edges of the Oil Cap

If that does not work, spray some lubricating oil on the oil cap’s outer edges. This will soften debris buildup on the oil cap’s inside parts. Then repeat steps 1 to 3 and see if it does the trick.

Hopefully, with this last step, you can successfully unstick the oil cap from its locked position on the engine oil port.

Again, how do you open a stuck oil cap? To open a stuck oil cap, wait for the cap to cool down. Then, apply oil to the lid. Try to loosen the cap. Once removed, clean the oil cap’s rubber seal, and apply lubricating oil.

How to Unscrew Your Oil Tank Cap?

oil cap stuck on jeep

You may be wondering how to turn the oil cap to remove it. Is it clockwise or counterclockwise? The right way to remove the oil cap is to rotate it counterclockwise. This is the right direction because the right way to put the oil cap is clockwise. 

So, to remove it, you have to do it in reverse. This is important because the oil cap prevents the engine oil from spilling out from the engine oil port. If you incorrectly put the oil cap in its hole, the engine oil will spill from its port.

So, if the oil cap was installed clockwise, you can loosen it counterclockwise.

You will push down on the oil cap and then twist it counterclockwise. If you have done the proper prep work, the cap will give way even if stuck.

What Can You Use to Remove a Stuck Oil Cap?

Removing a stuck oil cap from its hole in the engine is very frustrating. Don’t be frustrated, though, because there are some materials and tools that can help you unstuck a stubborn oil cap from its place in the engine oil port:

1. Lubricating Oil

Using lubricating oil is not used only for protecting the engine. It can also remove stubborn screws and caps. Many car mechanics and handypersons know this. So, this is your first option in removing a stubborn cap from its locked position in the engine.

First, you need to cool the engine because lubricating the oil cap while it is hot will not help you unstuck it. Once the engine is cool to the touch, lubricate the oil cap with enough oil that can penetrate the inner parts of the cap.

Use a clean rag or oil in a can to apply the lubricating oil. Wait about a few seconds to allow the oil to penetrate the insides of the cap.

2. Ice

Yes, you can use ice to remove a stuck engine oil cap. Using ice to do it is unorthodox. Not many people know that it has some power to do this difficult task. After the engine has cooled down enough, put some ice on the rim of the oil cap.

Let the ice stay on the oil cap rim to give it time to work. Ice has a wonderful way of cooling a material to contract its molecules. When the temperature is cold, the kinetic energy of a material decreases.

The atoms making up a specific material will take up less space because they contract. In other words, if the oil cap is made of metal and contracts, the volume that grips the engine port hole gets smaller. This will then enable you to move it easier in either direction.

3. Toothbrush

Don’t just throw away your old and used toothbrush. You can use it to remove the gunk that formed in the insides of the oil cap.

Sometimes, the debris is so hard and stubborn that removing it takes time. A toothbrush will make your work faster. You can also use a toothpick and toothbrush to complete the job easier.

4. Slip-Joint Pliers

A pair of slip-joint pliers can also help remove stuck oil cap easier and faster. It is also safer because it won’t damage the oil cap, even if it has not been moved for many months. To use this tool, you must also cool down the engine first.

Then cover the cap with a rag then, grip it with the slip-joint pliers, and move it counterclockwise. That should move the cap without damaging it. Remember to use enough force to unscrew the cap from its immovable place.

5. Channel Lock Pliers

You can also use a pair of channel lock pliers. However, you are advised to use this tool only after you have exhausted all the options, and you still can’t remove the stuck oil cap from its place. The reason is that this solution may damage the oil cap.

So, before using this tool, buy a replacement oil cap suitable to your old oil cap.

What Are the Reasons Why an Oil Cap Gets Stuck?

what to do if oil cap is stuck

If you don’t want to have trouble removing your oil cap, you should understand why it gets stuck in its hole in the first place so you can avoid them. Several things can lead to this situation:

1. Rusts

To some extent, the engine bay can be exposed to the elements. If this frequently happens in your car, rust can form on the components around the engine bay. That includes the oil cap, which is typically made of steel.

2. Over-tightening

You need to check the engine oil regularly and top it up occasionally. To do this, you must open it and close it again after work. Sometimes, in closing the cap, you over-tighten it. The next time you open it, typically after some time, you find it is already stuck.

3. Gunk

You are advised to change your engine oil every 7.500 to 10,000 miles. If you extend this period, your motor oil will get dirty. Dirty engine oil clogs engine parts, including the oil cap. Over time, this dirty oil will harden. If that happens, it will stick to the grooves of the oil cap like glue.

In Closing

If it’s hard to remove the oil cap, wait a couple of minutes so it can cool down. Then lubricate its edges with clean oil so its grip on the oil port lid will get loose.

Use a rag to strengthen your hold on the cap as you unscrew it from the oil port lid. After removing the cap, put some clean oil on its rubber seals so it won’t get stuck again.

The oil cap got stuck probably because you have not checked your engine oil regularly. Solidified oil will accumulate on the cap’s edges if this is the case. This oil buildup will get thick and harder over time. That’s the reason why it’s hard to remove it from the engine oil port.