Removing the cover and it runs great?

[Cool runnins]

Evinrude 1971 125 runs wonderfully when I remove the cowel but with it on its gutless. Doesn’t ever get up to speed just floods out. Noisy and dangerous with it off, Is this a carb issue? Any thoughts?

 

[jimmbo]

Sounds like a Cowl Air Inlet Issue, or an Exhaust Leak in the Cowl

 

[racerone]

Check for sparkplug wires arcing to the cover / latches.------Yes I know the cover is fiberglass.

 

[Cool runnins]

I will check that tomorrow and let you know what I discover