98 Ocean Pro carb mixture

kevhed

Cadet
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May 2, 2011
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98 Evinrude, new powerpack, optical sensor, new fuel lines/bulb, new plug wires. Question regarding a rough idle and mixture adjustment.

The factory manual says if it's idling rough (not sneezing or backfiring) it's running too rich. Turn idle screws in 1/8th of a turn, wait a few minutes etc., if no improvement, repeat on all cylinders.

I guess my question is - which cylinder do you start on? Is there a way to tell which carb might be running rich or just turn them all , 1 by 1, waiting a few minutes in between each adjustment?


Thanks
 

Daviet

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Sep 24, 2008
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8,958
Re: 98 Ocean Pro carb mixture

I turn one at a time and let it run for few minutes, if that doesn't help return the idle screw to it orginal position and go to the next carb. It can be a long process.
 

daselbee

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Jan 20, 2009
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2,765
Re: 98 Ocean Pro carb mixture

Factory manual is BS on this point. You will not see a difference in an 1/8 inch turn variation. You will MAY MAY see a 1/2 turn vaiation,...but MAYBE. It is not that fine a difference.

If you have a lean sneeze, identify the cylinder by putting two fingers in the carb throats, being consistent regarding placement of your fingers on all cylinders, or by putting a toothpick in the intermediate air jet. That will affect the idle mix enough to ID the culprit cylinder.
 

kevhed

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Joined
May 2, 2011
Messages
10
Re: 98 Ocean Pro carb mixture

Thanks for the replies.

Daselbee- I think I'm running rich, because it's rough. No sneeze or backfire.
Any tip for identifying the rich cylinder(s)?



Thanks again.
 

daselbee

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Jan 20, 2009
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2,765
Re: 98 Ocean Pro carb mixture

It will not hurt a thing to turn those screws in one full turn. Test. Then another full turn. Test. Soon, you will develop a lean sneeze, then back the screws out until it stops sneezing. It takes time and patience. It must be in the water, not on muffs.

Count the turns that the screws are at now so you can go back if necessary.

I have a pretty slick way to set the idle screws. I set them about 7 turns out to start, (real rich) then I reduce the idle using the idle timing screw til it barely runs. Maybe 450-500 rpm. With it idling so slow, then you can hear the small adjustments much better. One half turn definitely causes a change that you can notice. Make turn adjustments as required to get the smoothest idle without any lean sneezing, and then return the idle to 750 or so with the idle timing screw. adjust slightly if needed when back up to 750.

There cannot be anything else wrong with the motor, or this will not work right.
 

kevhed

Cadet
Joined
May 2, 2011
Messages
10
Re: 98 Ocean Pro carb mixture

Thanks Daselbee. Think I got idle squared away. Now starting new thread with dropping a cyl at wot.

Thanks
 
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