Why is this happening???

[21270]

I have a 93 4.3lx merc with carb and full closed system. I have had no heat, hesitation or bogging down problems. I pulled the plugs today and all six were dry black fouled!!!!! plugs (ngk), dist cap and rotor are all a month old. plugs had no smell of gas on them, just dry & black. Wires havent been changed and could be ??? years old (im second owner, had it 1 year). My weber 4brl has the three notches for rich & lean, currently on factory set notch (rich) mark. Should I change the notch to run a little leaner? Thank You!

 

[dragracer]

Re: Why is this happening???

Choke sticking partially closed maybe? Sounds like it's running real rich for some reason.

 

[vipzach]

Re: Why is this happening???

Here is a link to a web page that I found, that explains the different colors and conditions of plugs and why they get that way. <br /> http://www.centuryperformance.com/spark2.asp

 

[21270]

Re: Why is this happening???

Thank you for the web site, I will check the choke and wires. Maybe im not getting enough spark through the wires.

 

[Bondo]

Re: Why is this happening???

You May,.. Or May Not have plugwire issues,..<br />But that won't cause blackened plugs,.... Normally.......<br /><br />I'd Sooner think you have a Carb. Issue,.....Too big a Jets,...Too Small a Needles,... Stuck, or sticking Float,...or maybe the float is set Too High,..... Don't Know...........<br /><br />What I Do Know is,..... The 3 notches you speak of are Only for the Accelerator Pump..........<br />That's Not your Problem............<br /><br />I know that Mine(same as Yours) was Very Rich from the factory,.. You could Smell the Gas when trolling downwind,..... I went to Larger Needles,+ Now have No Smell,+ the Prettiest Cream & Coffee Brown Plugs................

 

[21270]

Re: Why is this happening???

Thanks Bondo, I do know that this carb has never been rebuilt. Maybe its time since its 12 years old???? In the weber fuel system manual they make it sound as if all you have to do is move the accelerator pump rod to the second or third hole and this would clear the rich symptoms, I guess not. How hard is it to rebuild these carbs Bondo???

 

[Bondo]

Re: Why is this happening???

It's the Simplest 4bbl. Carb. around,.........<br /><br />Go over Here ,+ Look around,............<br /><br />Even though the Name on the Carb. is Different,.........<br />It's the Same Carb.........

 

[21270]

Re: Why is this happening???

Thank You Bondo!