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Do Rubber Valve Cover Gaskets Need Sealant? (Answered)

The engine is an important part of a car. If you fix an engine inside, it is seen that there is a rubber accessory around the edge of the engine cover. It is called rubber valve cover gaskets. This is an important element of an engine to help it run properly.

If you replace any of these rubber valve cover gaskets, you may ask if you need sealant or not. Let us help you answer that question and provide some additional information that may come in handy for you.

Do rubber valve cover gaskets need sealant?

Technically, rubber valve cover gaskets do not need sealant. These are designed in such a way that they will properly seal themselves without any additional sealant. But it is common to see that people are using sealants like Permatex High Tack or Permatex No. 1 gasket sealant.

Rubber valve cover gaskets are seen in almost every car. It is an essential part of a car’s engine. It helps to prevent any kind of leaks and helps the engine to run properly by sealing the top lid.

Sometimes repairs are required inside the engine. It is seen that rubber valve cover gaskets get replaced as a matter of fact during these kinds of repairs. 

Therefore, after replacing it many people think about using sealant to keep it in place so that the lid can be properly set back again.

But it is not necessary to use any kind of sealant to keep the rubber valve cover gasket in place. It is designed in such a way that it will stay in place even when replaced with a new one. But still, it is common to use sealant by many repair shops and mechanics. 

Also, people tend to use sealants due to misconceptions in the community.

Why do you need to seal rubber valve cover gaskets?

Though it is not recommended, people use sealant while setting a rubber valve cover gasket. There are various reasons why people tend to use sealant. Here are some selected reasons why we think you may need to seal rubber valve cover gaskets:

To set the rubber valve cover gasket in place:

Rubber valve cover gaskets are designed to be set in place without any additional help from any other material. It sets in place around the engine lid area and helps to hold the lid properly.

But you might consider using sealant because according to many people it helps in holding the rubber valve cover gasket in place. If it stays in place, then it can do its job properly and fulfill the requirement that it needs to accomplish.

Prevent any kind of oil leaks:

An engine oil leak is a disaster that people do not want to face. It not only makes a mess in the ground and around the engine but also makes a huge loss for the car owner. 

As engine oil is expensive in a sense, it may cost a fortune for a car owner who has an oil leak. Also, it may cause damage to the engine as well.

Therefore, sealant comes into play. Sealant helps to prevent any kind of oil leak in the engine. Thus, the owner will not have to worry about any engine leaks at all.

Prevent any kind of air gap:

An air gap in the engine lid may cause a lot of problems for a driver. It may cause the driver to lose power rapidly while driving. It may also cause the driver to burn more fuel to reach the target speed. Also, it may cause engine damage. 

Therefore, you may want to seal the rubber valve cover gaskets properly with a good sealant.

Can you use a gasket sealer on a rubber gasket?

No, you cannot use a gasket sealer on a rubber gasket. Both gasket sealers and rubber gaskets have the same objective in an engine and that is to seal the engine lid properly in place. It also helps to prevent any kind of oil spills and prevent air gaps.

Using a gasket sealer on a rubber gasket may cause problems in the future. It may cause unwanted air gaps and oil spills as it will create excessive height in the engine lid. It may also cause the engine to damage which may end up as a costly repair in the end. 

Moreover, you may damage your car’s engine badly and it may become irreparable.

Can you use silicone on the rubber gasket?

You can use silicone on the rubber gasket. Silicon does not chemically react with rubber molecules. Therefore, you can use silicon on rubber gaskets if you want to.

It can be used as a sealant if you want to. Silicon is popularly used for household sealant jobs. It is commonly used in window glasses, bathtubs, pipe joints, and many more. As it is commonly found around, you may consider using it on a rubber gasket.

But you should keep in mind where you are using it. Silicon can react with gasoline, more specifically with petroleum. Both do not react well when together. So, you need to keep that in mind when using it on a rubber gasket.

What sealant to use for the rubber valve cover gasket?

There are multiple types of sealants available in the market to use for rubber valve cover gaskets. All have a unique feature that makes them different from one another.

You may ask which sealant you should use for your rubber valve cover gasket. Here are some selected sealants that we think you might use for your rubber valve cover gasket:

Permatex 22073 Ultra Black:

This sealant is particularly made for RTVs. This helps seal the rubber valve gasket of the engine and ensure a long-lasting, trouble-free, and leak-proof operation of your engine.

You need to keep in mind that the manufacture does not recommend using it for gaskets that are cut or where there is direct exposure to gasoline.

Permatex 82180 Ultra Black Maximum Oil Resistance:

This is another sealant specially made for RTV. This is designed to work on oily surfaces. This uses a non-corrosive formula that helps it to last long in your engine and is sensor-free.

Gasgacinch 440-A:

This is a go-to gasket sealant that is famous for its cheap rate and easy-to-use application process. The user can apply this using brush which ensures that you cannot put much. It works on all conditions and is flexible.

How to seal rubber valve cover gaskets?

There are several ways that you can follow to seal rubber valve cover gaskets. Here are the best possible steps by us that you may follow to do it:

Remove the old rubber valve cover gasket:

You need to peel off the old rubber valve cover gasket to reseal the engine lid again. Getting it off will be easy. You will just have to pull it off from the sealing spot.

Clean any gasket and sealant residue:

After peeling it away, you need to clean the sealing area properly. Any dirt or leftovers of the old sealant or valve cover may cause problems in setting the new one. You can use rubber cleaner and clean rags to clean it properly.

Put the sealant where the gasket will be set:

After cleaning it properly, you will have to properly put some sealant over the sealing area where the valve cover will be set. Follow the instructions of your sealant of choice. The instruction will vary depending on the brand and type of sealant you are using.

Put on the new rubber valve cover gasket:

When you are done putting enough sealant, place the rubber valve cover gasket in position. It will simply be set into place without any hassle if you have done all the previously discussed matters. Afterward, set the lid of the engine and bolt it into place.

How long do rubber valve cover gaskets last?

Most rubber valve cover gaskets last for around 20,000 – 55,000 miles of driving. The longevity of a rubber valve cover gasket depends on how your choice according to your car’s needs. 

If you choose the right one, your rubber valve cover gasket may last longer than the estimated lifespan by the manufacturer.

Can a leaking valve cover gasket cause low oil pressure?

A leaking valve cover gasket cannot cause low oil pressure. Although leaking valve cover gasket may cause oil spills over time, it will not cause low oil pressure in the engine. The reason is that it is not a part of the pressurized system and therefore has no influence over cylinder pressure.

Final thoughts

Rubber valve cover gaskets do not need sealant. The valve cover itself can seal itself properly without any additional help. But many mechanics or workshops may use sealant to set it properly. Though it may seem normal to everyone, this may cause some serious issues later on.