Johnson-99 stalls at low speed

[Swedie]

Hi all, I have Johnson 70hk -99 that runs well on idle and higher speed when it's warm.When starting the motor I doesn't sound like it's running "clean" its coughing but still running, after the motor has gain some heat it works. Pulling out from the docks at idle is fine but increase the speed 100-200 rpm doesn't. Out on the lake running idle speed in forward gear works fine but as soon as I increase to just over idle it coughs and dies. No problem to restart, running idle or higher speed is fine. Running 100 or 200 rpm higher then idle doesn't work.normal idle is 900-1000rpm.Installed new spark plugs.If anybody has any idea I am ready to try it out.

 

[Swedie]

Okay, now I have cleaned out the carbs, found nothing special appart from one of the carbs had quite alot more oil on the top of it.
One question I do have if somebody could answer it.
The low speed needle is set to 4 and a half turn out, but looking at the manual it is suppose to be only 2 to 3/4 out. Why would it be set to this and what is the benefit?