Rich/lean settings for beginners

[CaptainRonn]

I think I have my rich/lean settings all wrong I have a 62' 40hp Johnson There is only a slow speed idle setting which has me confused, shouldnt there be 2 idle settings? anyway, should I start in the middle and slowly move to the left or right, and should I be running the motor at the start speed, because when I pull the throttle any further back the motor just shuts off, this rich/lean thing is just confusing. Thanks for any help you can provide.

 

[Vic.S]

Re: Rich/lean settings for beginners

The carb fitted to your motor has just one mixture adjustmnet screw, for adjusting the mixture at idle speed.

There is an excellent item on the Engine FAQs board by Joe Reeves describing the adjustment of the mixture needles

See http://forums.iboats.com/showthread.php?t=167352


Trying to figure out the cause of your confusion

The mixture adjustment needle #41 has a knob #74 in this diagram

but once the needle has been set properly it should not normally need altering.

The idle speed is set by a screw on the port side of the case best described simply by saying it is part #70 in this diagram: