Home › Forum › Ask A Member › 1977 Johnson 2 hp 2R77C Carb › Re: 1977 Johnson 2 hp 2R77C Carb
Well, trying to adjust that high speed needle in the test tank is at best, frustrating…The engine always revs up great once the tank water has enough air in it to let the engine ventilate a bit.
I would go for the highest/smoothest sustainable RPM on the boat, then back it off 1/8th turn. Definitely dial in the high speed needle first, then set the low speed. You shouldn’t really need to readjust the high speed needle again unless your initial low speed adjustment was way off. But, definitely run the engine at high speed again after adjusting the low speed, make sure it accelerates OK from slow to WOT, and that it doesn’t stall out after coming back down to idle (slowly) after a WOT run.