Using Sea Foam through a vacuum line is easy and safe if you remember one thing. Liquids don’t compress and can cause an engine to hydro lock if too much liquid is applied. Always regulate the rate at which Sea Foam goes into the engine. Never insert the vacuum line into the bottle of Sea Foam, always pour Sea Foam slowly into the vacuum line.

It is important to make sure the engine is at operating temperature. Then find a vacuum line that feeds all cylinders, usually the PCV hose or the vacuum brake booster line may feed all cylinders. If you are in doubt as to which vacuum line to use, YOU MUST check with a certified auto technician.

After the correct vacuum line has been located, start engine and disconnect vacuum line. With engine at idle and at operating temperature slowly pour Sea Foam into vacuum line. It is important to control the rate at which Sea Foam goes into the vacuum line. The engine will labor while applying Sea Foam. Pour enough Sea Foam into the vacuum line to make the engine labor at idle, but not enough to stall engine.

After 1/3 to ½ can of Sea Foam has been induced into the engine, shut engine off and let sit (hot soak) for at least 10 minutes and reconnect vacuum line. After the 10 minute hot soak period, restart engine in a well ventilated area as exhaust may be extreme for a short time. Road test the vehicle immediately after start up, driving aggressively until exhaust looks normal. This usually takes up to 5 miles. It is always better and safer to road test car to clean the gum, varnish and carbon out of the engine.

By doing this you have done an intense carbon cleaning procedure to your engine. This operation is recommended once a year or every 15,000 miles.

The most frequently asked question about using Sea Foam is as follows: “After using Sea Foam in my oil, fuel, or through the vacuum line (to clean carbon from the combustion chamber) do I need to change my oil?” The short answer is: No you don’t have to change your oil after using Sea Foam in any application.

When using Sea Foam in your fuel or through the vacuum line for carbon cleaning your oil does not need to be changed. Using Sea Foam in your oil, at 1 ½ ounces per quart, is a safe way to clean a crankcase, free up rings or free up sticky lifters as you drive. Sea Foam is not a chemical engine flush and therefore, it will not damage internal engine components or plug the oil pick up screen. Sea Foam is a pure petroleum blend with no chemical additives and is safe for long term cleaning or short term pre-service cleaning.

Sea Foam is a blend of highly refined additive oils and is compatible with all motor oils including synthetics. It is safe for all internal engine components and will not affect any seals, gaskets or o-rings. Sea Foam cleans oil deposits and varnish in your crankcase by safely/slowly re liquefying the old oil residue so contaminants may flow and be filtered. The longer Sea Foam is in your oil the cleaner your crankcase will become. When adding Sea Foam to clean oil, for long term maintenance cleaning, you must check your oil periodically for color and clarity, when your oil looks dirty change it. Because you added cleaning oil (Sea Foam) to your oil you may have to change oil before the expected service interval.

When adding Sea Foam to dirty oil before an oil change, for best results use 1 ½ ounces per quart of oil at least 100 miles before oil is changed.

For more than 65 years, Sea Foam has been proven to be safe for use in all engines, both diesel and gasoline, and won’t harm gaskets, seals or other internal components of the engine, fuel system or oil system.  Sea Foam is a pure petroleum blend with no chemical additives.  Sea Foam has been endorsed by numerous engine manufacturers, and is recommended by thousands of professional mechanics and service technicians throughout the U.S. and Canada.

Sea Foam Motor Treatment is a highly effective and completely safe additive that improves the performance of your engine as it:

• Cleans entire fuel system, including carburetor jet or fuel injectors
• Cleans carbon from the combustion chambers and pistons
• Stabilizes fuels for up to 2 years
• Lubricates the upper cylinders
• Controls moisture in fuel
• De-ices frozen fuel lines
• Frees sticky lifters
• Frees sticky rings
• Controls moisture in oil
• Cleans P.C.V. components

All fuels leave varnish deposits, which over time build up, collecting carbon from exhaust and impairing the efficiency and effectiveness of your fuel system and combustion chamber components (pistons, valves, spark plugs.)  Sea Foam Motor Treatment was originally designed to remove this varnish build-up, and nothing does it better or safer than Sea Foam.

Sea Foam Motor Treatment can also be added to your oil to re-liquify oil varnish deposits and free sticky valve train components, enhancing the effectiveness of the lubrication system and adding to the longevity of critical engine components.

There are many factors that affect fuel mileage. (Like the auto manufacturers say, “Your mileage may vary.”)  However, common sense dictates that if you have an engine in which the internal components are clean and unhindered by carbon and varnish deposits or oil deposits, it is probably going to run more efficiently as well as generate fewer pollutants (assuming there are no other mechanical issues with your engine.)  Removing these deposits can also eliminate the pre-ignition knock that prompts the knock sensors in newer cars to retard the timing.  Mileage improves when the computer re-sets the timing towards top dead center.

Sea Foam gives your engine a chance to be as efficient as the manufacturer designed it to be, pure and simple.  If your engine is being affected by significant varnish and deposit build-up, you will likely see an improvement in fuel mileage with correct use of Sea Foam because you will have removed these hindrances to performance.  But Sea Foam is NOT promoted to be a “power booster” or “mileage enhancer” product as such.

Sea Foam is composed solely of three specially blended petroleum oils – each having specific functions such as lubricating, cleaning or moisture control.  There are no other chemicals (not even color dyes) included in the formulation.  Being of the same basic petroleum chemistry as the motor oils and gasoline you already use in your engine, Sea Foam is completely compatible with all engine components, fuels, lubricants and other additives you may have in your engine.  Sea Foam will not damage gaskets or seals, and will not interact in a negative way with motor oil or fuel, or the additives used in them.

In some cases, in engines where carbon deposit build-up is severe, it requires a more aggressive application of Sea Foam.  By directly pouring Sea Foam into the throat of the carburetor, or into the main manifold vacuum line that serves all cylinders, stubborn carbon and varnish deposits are soaked in pure Sea Foam, and are more effectively removed from cylinders, valves, pistons and rings.  WARNING - This induction application method requires extra care, and if performed improperly, can cause significant damage to your engine, which is why we recommend that you have a professional mechanic perform this procedure for you.

Carbon is leftover residue resulting from the fuel burning in the engine cylinder.  Most of the carbon residue formed by burning fuel in the cylinders is expelled through the exhaust valve and out the exhaust system.  However, over time as fuel varnish deposits collect on cylinder walls and on the tops of the pistons, small bits of carbon get imbedded into this varnish.  As this process continues, significant carbon deposits can accumulate.  Carbon retains heat, and some of these deposits remain so hot that they act like small spark plugs, prematurely igniting the air/fuel mixture that is injected into the cylinder before the piston has reached the correct position – a condition called detonation or pre-ignition.  Detonation can cause severe damage to the pistons, valves, sparkplugs and cylinder walls.  Sea Foam Motor Treatment dissolves the varnish which is the glue that holds the carbon deposits, and thus allows these deposits to be expelled safely through the exhaust system.

Sea Foam has been extensively tested and proven to work well in Ethanol blended fuels since they first appeared in the 1990s – even the newest E-85 blend.  Ethanol has the effect of stripping the protective layer of motor oil from the cylinder walls, so the addition of Sea Foam Motor Treatment to your fuel actually helps to combat this drying effect by adding upper cylinder lubrication that helps to prolong the life of your engine. Additionally, Ethanol burns faster, hotter, and makes about 18% less power than regular gasoline – and all are detrimental to your engine’s performance.  Sea Foam’s high temperature/low sulfur oil formula helps to slow down the burn rate (this is a good thing!) and reduces pre-ignition and detonation damage that can be caused by the use of Ethanol blended fuels.

Absolutely!  In fact, many professional mechanics use Sea Foam in their specialized fuel injector cleaning machines as the cleaning agent.  Regular use of Sea Foam in your fuel tank will help to ensure your injectors remain free of harmful deposits that can adversely affect your engine’s performance and fuel mileage.

Sea Foam is safe for home use in cars, small engines and recreational vehicles.  Anyone can realize the benefits of Sea Foam simply by adding it to your gas tank according to the directions on the can.  However, depending on the nature of your engine problem, Sea Foam recommends consulting with your professional mechanic to assess whether your situation requires more advanced diagnostic procedures.  There are some special application procedures that address other specific engine conditions. These special application procedures (called the “induction application method”) are described in other sections of this website, and can be performed by any mechanically competent individual having detailed knowledge of their engine’s fuel and induction systems. However, relying on your professional mechanic to perform these procedures is the safer choice.  But for the average automobile owner, routinely adding Sea Foam Motor Treatment to your fuel tank according to the instructions will give you the same benefits as the induction method, improving performance and prolonging the life of your engine – it just takes a little longer to see the results.

Sea Foam is safe for ALL commonly used engines – Automotive, Truck, Industrial, Agricultural, Motorcycle, Marine, Small Engines (lawnmowers, yard tools, etc.), and even Rotary (Wankel Type) engines.  2-cycle and 4-cycle as well as diesel engines are completely compatible with Sea Foam.

No – quite the opposite.  Sea Foam actually helps to clean the catalytic elements, restoring its efficiency, and reducing that “rotten egg” odor you occasionally smell from some catalytic converters that aren’t working properly