Lean-Rich mixture settings?

handle

Petty Officer 2nd Class
Joined
May 7, 2012
Messages
104
On my 72', 25hp Evinrude#25253r. Trying to find out on the rich/lean knob adjustment, with linkage removed how many turns out should the screw/needle valve be for a ball park setting? The knob only lets you make a small adjustment. I seem to be running on little less than one turn out. Whats the standard setting?
 

ddwilson

Petty Officer 2nd Class
Joined
Apr 8, 2012
Messages
116
Re: Lean-Rich mixture settings?

There is a sticky that explains the procedure, start @ 1 1/2 out and work from there, even then may have to get it on the water and adjust a little bit more.
Doug
 

OptsyEagle

Lieutenant
Joined
Sep 13, 2006
Messages
1,356
Re: Lean-Rich mixture settings?

With my motor I usually adjust it to the right spot by turning the knob and possibly repositioning the knob a couple times. Once I find the right spot, I reposition the knob so that it is in the middle of the range. So don't worry if your knob hits the max position before the carb is set right. Just reposition it to the min position and keep turning.

Hope that makes sense.
 

Aydelott

Cadet
Joined
Mar 15, 2014
Messages
21
Re: Lean-Rich mixture settings?

How do u know there set right I've turned mine all the way to the left an right with out the nobs so I have know idea where they go it's a 1958 7.5
 

JDusza

Ensign
Joined
Apr 21, 2009
Messages
934
Re: Lean-Rich mixture settings?

Pull the knobs off. They'll go back on later.
Close the needle valves by turning them clockwise until they stop.
Back each one out about 1 1/4 turns. 1 1/2 turns is good, too.
Try starting the engine in water.
Adjust high speed to be just a little rich for get up and go and adjust the slow speed for smooth and steady idle.
Do this final adjustment out on the water with a load on the engine.
Once the needle valves are where you want them, put the knobs back on at the mid-way positions.
J
 
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