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Sea Foam Motor Treatment

The chemical product known as Sea Foam is a strong petroleum-based engine treatment which cleans carbon deposits from the intake and exhaust, cleans gummy deposits out from inside the engine, and stabilizes the fuel.

Fluid Characteristics

ColorClear Yellow/Orange
OdorSimilar to Nail Polish Remover
ViscosityThin, Water-Like
Eye/Skin IrritantYes

How to Use Sea Foam

There are three ways to use Sea Foam, each of which focus on different areas of the engine.

    Fuel System

  1. Pour the contents of one can into a half-full gas tank (assuming the tank is roughly 8 to 25 gallons).
  2. Use the vehicle until the gas tank is almost empty before filling it back up.
  3. If the engine starts knocking, too much SeaFoam was added. You can dilute the mix by adding more gasoline to the tank.

    Intake Induction

    Warning: using too much Sea Foam in this method can vapor lock an engine, which causes costly damages. If you aren't familiar with engines and/or are not confident that you can use the right amount of Sea Foam, do not attempt this method.

  1. Find a vacuum line which leads to all cylinders, and prepare it for use by diconnecting it and using a small funnel or the line itself.
  2. Turn the engine on, and let it warm up. With a vacuum line off, it may idle abnormally, and the "Check Engine" light may come on when the system detects a vacuum leak.
  3. Find a way (other than via the engine computer/OBD connection) to run the engine at a slightly higher RPM than the idle level while the procedure is performed. While this isn't mandatory, it helps the Sea Foam coat the metal inside the intake, breaking away more carbon deposits.
  4. Slowly drip very small amounts of Sea Foam into the intake, careful not to let too much get in at once.
  5. Shut off the engine, reconnect the vacuum line, and (if possible and/or necessary) clear the vacuum leak code. Wait about five minutes.
  6. Start the engine and allow it to run until the exhaust blows out the last of the Sea Foam smoke (burned up carbon deposits, etc.) or after ten minutes if the smoke clears early or none appears at all.

    Engine Flush

  1. Coming soon!

How to Use Sea Foam Motor Treatment Video

Fuel Line Test

Steve from Cars Simplified ran an independent test of five motor treatments, including SeaFoam Motor Treatment, and these were the results:

Does SeaFoam damage fuel line?