[Chester B. Stone, Jr.]

When I ran twin twin marine 6-71s, I used Delo 100, 40w. This oil was especially developed for 2-cycle Detroits. In my Series 60, I use Delo 400EL, 5w40 which is synthetic and the best price I have found is a Walmart at $20 per gallon. Caution, Delo 400EL 15w40 is not synthetic.