Will Sea Foam break down or not be good after a certain period of time? [SOLVED]

Thanks for the question, Robert! Sea Foam Motor Treatment lasts a long time. An unopened can will work for decades. Once opened, if the cap is closed tight and the liquid is clear, it will still be fine to use for many years. I’d go ahead and use it.

Here is a video that explains more about the shelf life:
Does Sea Foam Motor Treatment have a shelf life?

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