Leaking Engine Gaskets

Sometimes when our cars begin to leak fluid we can blame leaking engine gaskets. Often these fluid leaks begin as seepage and developed into a problem that needs to be addressed for the health of the vehicle and the driveway or parking area.

Picture of engine gasket leak

Engine Gasket Leak


For as long as there have been engines there has been a gasket. Over the years the technology has advanced that makes these sealing components more efficient. But every once in a while when they try a new technology sometimes it’s actually a step backwards.

A quick example of this is just my personal opinion. The latest in Gasket technology sometimes referred to as a composite looks and feels like plastic. An example of a step backwards is in the reliability of the Gasket in the General Motors V6 intake manifold. This part looks like a strip of plastic with embedded rubber seals.


Using this type of technology the bolts are torqued very light to prevent cracking of the sealing component. The lighter the bolts are torqued the more of a chance it has to back off or loosen.

And if you pop the hood on a GM six cylinder vehicle chances are you can find evidence of coolant leakage from around the intake manifold. This problem is most evident on late 90 and early 2000 model years.

About engine gaskets

A gasket in general is used to prevent gas or liquid leakage between two parts that are bolted together. They can also serve as spacers to provide proper clearance between the two items that are bolted together.

When it comes to leaking engine gaskets you will find that the materials that they are made out of will fall into a few categories. The first one being a hard one such as steel or other types of metal. These would be used in applications such as exhaust manifolds and cylinder heads that generate extremely high temperatures.

Picture of differential gasket

Differential Gasket

You will still find some soft gaskets that are made of materials such as cork or rubber or a combination of the two. Some people would also throw silicone RTV and other compounds that come in a tube in this category as well. I personally avoid using tube sealers whenever possible because in my opinion it is the least reliable.

Some of the best gaskets on the market today would be a formed or molded silicone type. If you notice this type of sealing gasket can come in three colors. Black is considered for general applications. A blue color gasket is often considered a specialty gasket that can be manufacturer specific. And the most common would be a red or dark orange. This type of silicone gasket is used in high temperature applications.


Replacing leaking engine gaskets

In my opinion one the most important things about sealing a leak on the engine is finding the right replacement gasket. I prefer to use factory original parts whenever possible. In a pinch I will use an aftermarket part.

But I will never use silicone from a tube instead of a gasket. There are times when you will need to use silicone or RTV. This is when the factory has applied it to the sealing surface. But if there is a gasket you want to replace it with a new one.

Often I see driveway mechanics trying to reuse old Gaskets. This is not recommended even if the old Gasket appears to be in good condition. It just will not seal as good as a new one because it has all ready been compressed.

When you’re installing new sealing parts taking the time to clean the surfaces is extremely important. The new parts will seal best when used on clean surfaces. Make sure you get all of the dirt, oil deposits, loose rust, old sealer and even the tiniest pieces of the old gasket material off of the sealing surface.

I hope you found this article helpful. If not give me another chance. This next link takes you back to the online auto repair blog from this page about leaking engine gaskets. Review a few more articles about automotive repair and how the Internet can help you fix cars at home.

One comment

  1. Great web site and a best article..posts like this will help people to solve problems them self..thanks for the great post

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