I got our 83 50HP Evinrude out on the lake tonight after a rebuild of both carbs and replacing all fuel lines. Compression is good at 120 on both cylinders and spark is bright blue across 1/2". I am only getting 3500-3800rpm at WOT and suspect this is a prop issue. My current prop is a 11 3/4 x 17. Which way do I need to go to increase RPMs?
This is on a pontoon boat.
This is on a pontoon boat.