Does Seafoam Clean Fouled Spark Plugs? (Explained)

Seafoam has been the go-to product for car owners interested in cleaning and lubricating their vehicle’s fuel systems.

It removes deposits and residues on fuel passageways, chamber areas, pistons, and valves. However, can you use it to clean fouled spark plugs?

A fouled plug contains a substance that resembles carbon or oil. This substance often comes in the way of preventing the plug from sparking correctly.

Even though fouled spark plugs can be cleaned and re-used, they often don’t work as efficiently as they did when they were new.

That’s why when your spark plugs become fouled, the best solution is to replace them. It’s not always when you may have the money to do so, and that’s where Seafoam comes in handy.

Seafoam is one of the few additives that you can use to clean a fouled spark plug.

When you add Seafoam to treat your fuel system, as it moves across the pistons and valves, it will also treat fouled spark plugs if there are any.

You can however take it off and clean the oily or carbon substance with a Seafoam and wire brush to scrub the substance. That should do the trick.

does Seafoam clean fouled spark plugs

Can Seafoam Ruin Spark Plugs?

There have been complaints launched against Seafoam that it can damage spark plugs. We will get more into detail about that and how it may happen.

But to answer this question. Seafoam won’t damage your spark plugs. As a matter of fact, it also removes residue buildup around them when treating the engine.

A lot of car owners have been treating their engines with Seafoam and there have been no complaints so far. Therefore your case won’t be any different. The Seafoam will even prolong the life of your spark plugs.

Should I Replace My Spark Plugs after Using Seafoam?

We don’t see a reason why you should do that because the role of Seafoam is to treat the engine and its components, not the exact opposite.

However, there is something you need to know about Seafoam and its ability to foul a spark plug.

There is a recommended method of applying Seafoam to the spark plugs and the procedure entails elevating the RPM when applying the product.

According to the instructions on how to use Seafoam, when the RPM is elevated, the engine draws a lot of air thus allowing the product to spread to the upper parts of the engine.

Failure to elevate the RPM may result in having too much liquid in a chamber and this can foul a spark plug.

Similar to any car product, always follow the instructions provided by the manufacturer. This will prevent you from having any issues later on.

Will Seafoam Foul Spark Plugs When It’s Run through the Brake Booster Line?

If you discover that your spark plugs are fouled after applying the Seafoam treatment then there is a huge chance that they already were.

Seafoam treatment even when used through the booster line, doesn’t often affect the plugs in any manner. Even as the smoke comes out, and the product soaks into the brake booster line, the plugs remain unharmed.

What you should be most worried about is running the Seafoam treatment through the brake booster line and not the fuel system.

The latter is the recommended way of doing it. If you are considering running it through the brake booster line, chances are you have been around for a while, and you are used to the processes recommended by the old service stations.

The reason why we don’t advise our readers to run Seafoam through the brake booster line is that it is a petroleum-based product.

And the brake booster line wasn’t meant to have petroleum products running through them. The old systems were okay, but anything made from the 90s going up needs to be treated through the fuel system.

What about Treating New Spark Plugs with Seafoam?

Even though there is no likelihood of Seafoam ruining your brand new spark plugs, if you are worried, then the best course of action is to change the old plugs after performing the treatment.

As a car owner, what you will come to realize in the future is that the more things you try on your car, the better you learn how to take care of it.

You will obviously come across tips on car forums or from friends and colleagues. But learning and discovering new things about your vehicle gives you the experience that you need to take better care of it.

That’s why we are advising you to replace your old plugs after performing the Seafoam treatment. So that even if you are worried about them being fouled, you will have nothing to lose.

During treatment, the carbon residue will be coming off and in that process, it may re-attach to the plugs. To prevent that from happening, you can always Seafoam first and then install new plugs later on.

Another thing you need to take note of is that the amount of carbon that will be released depends on the care you have been giving to your vehicle.

If you have never treated your fuel system, the carbon that will come off will be massive. You may even have to perform two or three more treatments for your fuel and engine system to be fully rid of carbon buildup.

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Why Did My Spark Plugs Get Fouled after Seafoam Treatment?

There is a huge chance that your spark plugs were already fouled even before you used the treatment. When it comes to Seafoam, there are two types of users; the careful car owner who always treats their fuel system regularly.

And we have the one who has just discovered their fuel and engine system is clogged with carbon and oil buildup. If you belong in the latter category, then this question mostly applies to you.

Spark plugs can get fouled because of many reasons such as damaged valve guide seals, worn-out engine cylinders, and damaged piston rings.

All these things lead to the same outcome. If you rarely take care of your car then these issues may be the ones causing your spark plugs to get fouled.

To rule out whether Seafoam is the one causing your spark plugs to get fouled, always check them before performing the treatment.

Spark plugs are used to ignition the engine, control by computer unit<br /> Spark plugs are important for engines that use gasoline. Illustration info graphic.

Can Fouled Spark Plugs be Cleaned and Re-used?

Yes, they can, and you can use Seafoam to clean them. When a spark plug is coated with carbon or oil, a strong additive can clean it.

However, even if it is cleaned, its functioning capabilities will be interfered with and the efficiency will decline. The reduction in its abilities worsens if the spark plug has outlived its lifespan (100k miles and more).

It is up to you to assess whether the spark plug is in great condition and if cleaned, will it be able to facilitate the smooth running of your engine.

Never hesitate to replace old plugs because, unlike other engine components, spark plugs aren’t the most expensive car parts.

Can I Use Brake Cleaner Instead of Seafoam?

There is a wide range of cleaners that you can use to remove oil and carbon from a fouled spark plug. Other than Seafoam, brake cleaner is perfect for removing stubborn deposits.

Make sure that you scrub the spark plugs with a brush as you pour the brake cleaner on them. Before returning the spark plug to the engine, ensure that it is clean and dry.

You don’t want to add the wrong products to your engine as the results can be catastrophic.

Don’t Spark Plugs have Self-Cleaning Abilities?

Yes, spark plugs are designed to be self-cleaning. That is, when they create a spark as the engine runs, the heat burns off anything that may be surrounding it.

Your spark plugs self-cleaning abilities activate themselves when you take a drive from your home to the nearest grocery store. With this in mind, you may be wondering, how does it get fouled?

You can refer to the above-mentioned causes of fouled spark plugs. Issues such as damaged piston rings or valve guide seals will affect the spark plugs.

How Can I Identify Fouled Spark Plugs?

As unbelievable as this may sound, you will know a fouled spark plug when you see it. On the tip, you will see a black deposit that resembles carbon.

It can either be oily or dry. A fouled spark plug can still carry it its duties. However, the engine won’t run efficiently. And it may cause even more serious problems in the future.

Therefore, immediately clean a fouled spark plug the moment you notice it. And if Seafoam or brake cleaner doesn’t work, replace the spark plugs.

A pro tip that can help you in cleaning the fouled spark plugs is by using a brass wire brush. This penetrates the tiny spaces at the tip of the plugs to remove all carbon deposits.

A knife can also be used to scrape off the deposits. Avoid by all means using excessive force as this can damage the mechanism of the spark plugs.

Is WD-40 an Ideal Cleaner for Spark Plugs?

If you are dealing with a fouled spark plug, you have so many cleaning options, including WD-40. Other than getting rid of stubborn deposits, WD-40 prevents corrosion of the spark plugs.