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Seafoam Engine Treatment for Gas and Oil

I've worked in machine shops and mechanical bays. I've gained a lot of real-world knowledge that I'm eager to share.

Seafoam engine and oil treatment system is really one of the best additives out there.  People really do swear by it.

Seafoam engine and oil treatment system is really one of the best additives out there. People really do swear by it.

Seafoam Oil Treatment

When I was living in the Midwest, an old farmer told me about an engine and oil treatment product called Seafoam that he had been using for years and swore by. At first, I thought he was crazy, using a product in both his oil and his gas tank. But then I tried it, and I also read the many testimonials out there from others who had used it, and I've been sold ever since.

Seafoam is an additive that basically functions as a fuel system cleaner as well as an oil system cleaner. It can and should be used for both systems of the car and can really fix idling problems, poor fuel economy, gunk in the oil, and clogs in your injectors.

Seafoam needs to be used with caution, however, because of how powerful of a compound it is. This article will attempt to explain the safe practices for using it and what not to do. But if you have any hesitation, you could always just buy a bottle, take it into your mechanic the next time you go for an oil change or some procedure, and ask how much they'd charge you to use it in the vacuum line and intake manifold. It's pretty easy to use in the gas tank; just read the instructions.

Using Seafoam in the Crankcase for Engine Oil Sludge

One way that Seafoam can be used is for cleaning deposits out of your crankcase and oil system. In older cars, sludge can build up over time in the crankcase and other places where oil flows. Seafoam will help to dislodge and re-liquefy these buildups so that they can be filtered out and removed. The best practice is to use 1.5 ounces of Seafoam for every quart of oil.

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Please note though that if you use Seafoam in your engine oil, you'll have to almost immediately change your oil. One thing that I like to do is to add Seafoam to your oil just before I go in for an oil change. I pour in the directed amount and then drive off to where I get my oil changed, which is about 20 miles or so, which is a little bit less than recommended. Ideally, Seafoam should stay in the oil for between 30 and 60 miles of driving. This gives it enough time to break up the sludge in the oil and then to get changed out with the old oil.

The only thing you need to make sure of is that you change your oil filter as well. The Seafoam will re-liquify the old sludge and make your oil very dirty, so make sure you don't drive too far with it in your oil like this. Seafoam is safe for synthetic oils as well.

Using It in Your Gas Tank

Seafoam can also be added to your gas tank. When used in this way, it will help clean your fuel injectors, can boost fuel economy, and give you a better idle. Approximately one ounce of Seafoam should be used for every gallon of gasoline in the tank. Just pour in the directed amount and drive normally. It will clean the gunk deposits as you drive and will slowly begin to boost your fuel economy and clean your fuel injectors. In addition to this, if there is water in your gas tank, the Seafoam should help to eliminate that as well, which is a nice bonus. If you're using Seafoam for the specific purpose of wanting to remove water from your gas tank, use the same amount as directed above, one ounce per gallon of gas.

Using It in the Intake Manifold and Vacuum Line

Seafoam can also be used in the intake manifold to clean your valves and your intake. This is a tricky place to use Seafoam since you have to identify your vacuum line and disconnect it. Not only that, but you have to be able to identify a vacuum line that feeds all cylinders. The two lines that generally do this are the PCV hose and the vacuum brake booster line. If you aren't sure how to locate these lines, it's probably best to leave this to your mechanic. If your engine doesn't have vacuum lines, a spray version of Seafoam is also available that can be used in a similar fashion.

Seafoam can be poured directly into the vacuum line. The car should be turned on and running at operating temperature while you pour the seafoam into the vacuum line. Pour it slowly, making sure not to stall the engine. Once about a third of the can is in the intake, shut off the engine and let it soak for 5-10 minutes. Then turn the car on again. Your exhaust should look extremely dirty. You need to drive aggressively for about five miles to rid all of the carbon that has been released from the engine components.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

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