Sea Foam is absolutely safe for your diesel engine when used as directed. Sea Foam has been the choice of professional diesel technicians for more than 60 years. Sea Foam Motor Treatment is 100% Petroleum, NOT A CHEMICAL, and therefore is safe to use in all diesel fuel mixtures.

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.

Sea Foam, when used in Diesel fuel, cleans fuel deposits from the fuel system and carbon from inside the engine safely. It also adds lubrication and controls moisture when added to diesel fuel at one ounce per gallon. Another use for Sea Foam in Diesel applications is cleaning fuel injectors. This is accomplished by getting engine to operating temperature then shut off. Remove the fuel filter (replace filter if needed.) Empty all diesel fuel from filter or filter housing and fill filter or housing with straight Sea Foam. Reinstall filter on engine, making sure there is no air in filter. Start engine and let run about two minutes, then shut engine off and let sit about 5 minutes. This is called a “HOT SOAK” letting the Sea Foam soak into the carbon. After the “hot soak” period, restart the engine and road test, driving aggressively for about 5 miles. This will clean carbon from the injectors and the combustion chamber inside the engine. Sea Foam can also be used in oil for cleaning the crankcase. Adding Sea Foam to your oil will clean oil deposits and varnish from your crankcase, free up sticky lifters and clogged oil control rings. Add Sea Foam to the oil at one pint to four gallons of oil. Then drive vehicle a minimum of one hour before changing oil.

Sea Foam is very safe and effective in the ways described above. Most people that own and work on Diesel cars and trucks know that no liquids can be used through the air intake system of a Diesel engine including cleaners and starting fluids. If this is done to a Diesel engine it can cause major engine damage including Hydro-Lock or uncontrolled engine acceleration known as “RUN AWAY”. Do not add Sea Foam to the air intake of a Diesel engine!!

If these simple instructions are followed, Sea Foam will effectively and safely clean your fuel system, injectors and the crankcase when used in Diesel engine applications.

Adding Sea Foam to your diesel fuel tank provides the following benefits:

Adds lubricity to the fuel, protecting moving parts from excessive friction damage

Controls moisture in diesel fuel

De-gels frozen diesel fuel

Cleans fuel residues from your fuel system components

Sea Foam cleans the fuel pump and lubricates the O-rings

Sea Foam cleans the pintle valve in your injectors and restores the injector’s spray pattern (this is where all the power and smoothness comes from in a diesel.)

Cleans carbon deposits from the combustion chamber

Stabilizes diesel fuel up to 2 years (at average 1 ounce Sea Foam /gallon diesel)

All fuels leave a residue in the system that collect contaminants and hinder proper operation of that system.  Sea Foam helps keep the system operating properly by making those residues dissolve gently back into a liquid state, allowing those contaminants to be filtered out of the fuel system.

Yes, Sea Foam is safe to use as instructed with any diesel fuel recommended by engine manufacturers.  Low Sulfur and Ultra Low Sulfur fuels have lower lubricating characteristics than older high-sulfur diesel fuels, and also tend to absorb atmospheric moisture more readily.  Using Sea Foam Motor Treatment helps to counteract both of these negative characteristics.  Sea Foam adds lubrication to limit friction damage that can be caused by these new fuels, and helps control moisture build up.

Yes - Sea Foam is great for use as a diesel engine crank case cleaner in conjunction with an oil change.  Sea Foam dissolves varnish deposits that hold carbon, ash and other contaminants in the oil. Simply add 1 can of Sea Foam to each 2.5 gallons of oil and run for 30-60 minutes before changing the oil. More contamination will be removed with the dirty oil leading to reduced engine wear between oil changes. The concept is simple - if you start with a cleaner crank case, it will take longer for the oil to become dirty.

Using blended 5% Bio Diesel with available mandated Low or Ultra Low Sulfur Diesel Fuels does not change the way Sea Foam Motor Treatment is used.  Sea Foam Motor Treatment is 100% Petroleum, NOT A CHEMICAL, and therefore is safe to use as instructed in all diesel fuel mixtures.