How long can I leave Sea Foam in oil [SOLVED]

What will happen if I didn’t get engine oil changed within 300 miles of adding Sea Foam to the oil?

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Jim D.
Jim D.
1 year ago

Good question, Brian.

The Sea Foam itself is safe to leave in there for the life of the oil. It won’t harm anything and will continue to clean and lubricate. That said, here’s why we recommend adding Sea Foam 100-300 miles before an oil change:

Sea Foam in oil works to reliquefy residues and deposits so they can be drained away with the old oil. It’s a very good cleaner. Adding Sea Foam 100-300 miles before you change the oil does two things:

  1. Gives the Sea Foam time to clean.
  2. Lets all the liquid crud (the residues and deposits that Sea Foam cleaned and reliquefied) drain away with the old oil. That way the dirty oil is not circulating in the engine for too long.

Check the color of your oil. If it’s dirty, go ahead and change it. If it’s a healthy color, just keep checking it periodically as you normally would and change it when it gets dirty or you reach the recommended oil change mileage.

Hope that helps!


7 months ago

I’m trying to flush sludge from my engine. I want to do a quick flush, I was wondering if it would be safe to add reccomended amount of 5 ounces for 300 miles, then rest of the bottle 30 minutes prior to an oil change? This is my second flush in two months, I used Liquid Molly, but felt that a longer lasting cleaner would be better for remaining residue.