Idle Mixture Issues...

[gregstukey]

So, I was adjusting my idle mixture and now I'm getting excessive exhaust, a lot of black exhaust residue under the swim deck and on the transom along with a lot of crud in the water. I was wondering if this meant I was running to rich or lean and how to fix it. Also, I was wondering the relationship between the idle mixture and idel speed--are they relatively independent of each other or do they work together exclusively? I'm trying to obtain a better understanding of these two screws...

Thanks,
-Greg

1992 Cobra 5.0 V8 with a Holley 2 barrel.

 

[Haut Medoc]

Re: Idle Mixture Issues...

Too rich......​

 

[gregstukey]

Re: Idle Mixture Issues...

idle mixture screw in? or out?

 

[180shabah]

Re: Idle Mixture Issues...

in

You need to get a shop tach, vacuum guage, and a manual, then all will be clear...

 

[gregstukey]

Re: Idle Mixture Issues...

have manual oem cobra---still not too clear on the relationship...no tach but anyway, ...just want the smoke to chill out... if i adjust the mixture does that mean I HAVE to adjust idle speed---or when mixture is good set my idle speed last? the latter makes more sense to me but like I said I'm a little hazy on it...

 

[180shabah]

Re: Idle Mixture Issues...

Adjust mixture
adjust idle speed
set timing
readjust idle speed if needed

All of this is on a warm engine

 

[Silvertip]

Re: Idle Mixture Issues...

If the engine is making that much black smoke I doubt it's an idle mixture issue. Are you sure the choke is open?

 

[gregstukey]

Re: Idle Mixture Issues...

its not so much "black" smoke as it is excessive exhaust and yes, choke is choking...

 

[180shabah]

Re: Idle Mixture Issues...

...and yes, choke is choking...

Easy there speed racer....

It may be "choking" too much, causing an excessively rich condition.

 

[gregstukey]

Re: Idle Mixture Issues...

the boat was performing great before I messed with it. no smoke and ran smooth. I shouldnt have messed with it but I did in an effort to understand my boat a little better (backfired). im just trying to get it back to where it was...

 

[MikDee]

Re: Idle Mixture Issues...

When warmed up, Adjust mixture screws to the highest engine rpm, that's it! Then adjust idle speed screw to specified rpm, you're done.

 

[gregstukey]

Re: Idle Mixture Issues...

Perfect! Thank you so much.

 

[Bondo]

Re: Idle Mixture Issues...

the boat was performing great before I messed with it.

Ayuh,................

Life at the iboats forums in 1 sentence.......................................

 

[gregstukey]

Re: Idle Mixture Issues...

yep....i duffed it. shoulda left it... such is life...