Re: 1965 Evinrude Lightwin – Speed Question

[Don]

Papster is right, you can’t build a skyscraper on a sand foundation.
You should definitely check the compression, and the spark should be able to jump a 1/4" gap while cranking.
Like I said, that needle valve looks incorrect, which may be adding to your idling problem. You need to check the throttle plate sycnronization and make sure the butterfly is closing fully (and not binding) at idle as well.
I don’t know how much you paid for the engine, but you might consider the sellers offer of a refund if you/he can not make it idle right.