Does Sea Foam have a shelf life or lose its veracity after a while? [SOLVED]

Thanks for the question Elizabeth. Sea Foam is made from petroleum and will not change if sealed from the oxygen atmosphere. It the cap is sealed, it will last several decades. If the seal has been removed and the cap is on secure you can expect it to stand up for a few years as long as you know where it came from. I would not hesitate to use as long as the fluid is clear.