Mid 80s 15hp Evinrude question

[cckjone]

Sorry for the newbie question but I just purchased new boat with 15HP Evinrude. I looked up the model number and I think its 85. (E15RCOB) My question is...what the heck is that knob thingy next to the choke for? Does it adjust the Idle? It will rotate one full turn from lock to lock but I can't really tell if I'm adjusting the idle or not. I ordered a owner's manual ($20... give me a break) but the 4th is coming up and I'm kinda concern about running the engine very long without knowing what the function of this knob setting is. By the way the engine runs like a champ but any help explaining the function of this mysterious knob, to me at least, is much appreciated.

 

[Reel Appeal]

Re: Mid 80s 15hp Evinrude question

Sounds to me like your describing the low speed adjustment.This controls the rich/lean mixture when motor is running slowly.High speed is factory set and cannot be adjusted.Turning the knob clockwise will lean out the mixture,counter-clockwise will richen.Set it where the motor runs best and responds smoothly to a quick throttle twist(ie:from start to fast)

 

[cckjone]

Re: Mid 80s 15hp Evinrude question

Holy cow...that was fast response! Thanks Reel Appeal. I think you're right. Since I was running at full throttle I couldn't detect any difference but I did notice at low speed that it would quite if I didn't keep the knob in the center position. Thanks,