Our 2000 30 merc 2 stroke had sat for a number of years before we got it and then because of circumstances, sat for another few years. Motor had few hours. Finally got it to mechanic to get it started late last year, had an electric issue that he fixed. We had carburetor off, didn't look too bad, but was a little glassy looking. In any event, have been using Sea Foam with every gas fill up. The motor seems strong and no fuel issues other than having to adjust lean idle. It was running too lean. Lubricates upper cylinders also. For a motor that has sat, I would recommend. I'm sure other brands do the same thing.