Re: 1957 Johnson AD-11 not getting fuel

[Don]

Well, you have the most important ingredient for tweaking the needles: motor mounted on the boat and in the water running as it normally is used.
In any event, fine tune the high speed needle first. Run the engine in gear at WOT with the normal load in the boat for a minute or so before gently leaning out the high speed mixture, allowing a few seconds between each 1/8th turn of the needle. The engine will start to lose RPM when you have leaned it out too far, probably best to leave the high speed needle about 1/8 turn rich from its optimal setting.
Now idle the engine down in gear and let it run for 10 seconds or so before attempting to tweak the low speed needle. Do the same thing, gently lean out the low speed needle as the motor smooths out and RPM increases. You will know when you have gone too far when the engine starts to sneeze/cough. Again, leave the needle about 1/8th turn rich from its optimal setting.