The outboards are late 80s so not any kind of "new generation" stuff. Except for environment issues, would saber pro work for the outboards as well? Will only run a gallon or two per summer. If I didn't see a lot of soot and oil leftovers on them using old shell tcw2 oil, I wouldn't be concerned, but they look like they have an oil/soot flu on 50:1 tcw2.