Black soot on ground at start up

[Ed Martin]

Another video. Very clear directions. Also works for non electric chokes.
https://www.google.com/search?q=how...US751&oq=how+to+adjust+the+electric+choke+on+

Thanks Dave. I am making progress (with your help). Yesterday I looked at it again and found the index mark on the cap … I had rotated the cap over a period of weeks, more and more CCW to where the cap mark was so far CCW past the notches on metal part that I could not even see it. I was trying to keep the fast idle on longer because once I pulled out and took my foot off the throttle the curb idle was not enough to keep it from stalling until the engine warmed up. So now I adjusted the cap to just close without tension and I'm waiting for a dry day here in NC (hopefully next weekend) so I can see how it does. But now I'm thinking there won't be any fast idle (after I hit the pedal and the fast idle cam disengages) and don't see a fix for that. I had seen this video you sent but it is good to see it again...thanks.

 

[toolmanmike]

So that we are all on the same page, what carb do you have? They all operate very similar but each may have it own little quirk. The choke coil makes the butterfly close and through the linkage will set the fast idle cam to a higher step. You may have to adjust the fast idle set screw to get the fast idle speed you need. Because the linkage is slotted, you can kick it off of fast idle at any time. The fast idle cam just spins on the screw and the heavy end of the cam falls to the bottom of it's travel to where there is no step for the adjustment screw to catch on.

 

[coloradodave]

Ed, Just reread your original post. The problem started when you increased tension on the choke blade to make it stay on fast idle longer. Please take a clear up close picture of the passenger side and driver side of your carburetor so we can see the factory set-up. Thanks.

 

[toolmanmike]

Ed, Just reread your original post. The problem started when you increased tension on the choke blade to make it stay on fast idle longer. Please take a clear up close picture of the passenger side and driver side of your carburetor so we can see the factory set-up. Thanks.

It will stay on fast idle until you tap the gas pedal. It will stay for days if you gave enough gas in the tank.

 

[toolmanmike]

The choke coil will make the fast idle work but it will not take it off fast idle. You need to study the operation to understand how the choke and fast idle works. Re-read the posts above. I have written many lines of theory for you. Once you understand how simply it works, adjusting it is a snap.

 

[Ed Martin]

Ed, Just reread your original post. The problem started when you increased tension on the choke blade to make it stay on fast idle longer. Please take a clear up close picture of the passenger side and driver side of your carburetor so we can see the factory set-up. Thanks.

Dave and Mike: This is great, I appreciate the input you guys are giving me. I have adjusted the cap to notch 4 from the front (hope you can see from the photo). The mark on the piece of tape is what I was using to keep track of several changes since I could not find the reference mark on the cap until this week because it was so far CCW past the notches and I had put my mark even past where the real mark is in the cap now at notch 4. So now it is much more lean. I really think this will stop the black soot. I understand the fast idle stays until I tap the gas. Doesn't it come off fast idle one step at a time on the cam until it's fully warm? My problem before is that it wasn't staying on fast idle very long (that's why I adjusted it so far CCW to rich) and the engine was stalling when I had to come to a stop before it got warmed up. Here's some photos... there are supposed to be three, but can't get the carb from pass side to upload. It's a 80457SA 600 cfm Holley.

 

[Ed Martin]

The choke coil will make the fast idle work but it will not take it off fast idle. You need to study the operation to understand how the choke and fast idle works. Re-read the posts above. I have written many lines of theory for you. Once you understand how simply it works, adjusting it is a snap.

Thanks Mike … see my response to you and Dave just now. I had trouble uploading the photos, don't know why there are so many. There are three and I think the pass side carb IS there.

 

[toolmanmike]

I see the index mark on the cap it looks one notch right from center. (looking at it straight on. That is rich I believe. ) Never adjust it more than 1 notch at a time. The caps always had a arrow and Rich/lean marked on it as to which way to go. Those Holleys have the fast idle cam behind the choke assembly. (the red plastic cam. it should be free and move with gravity when you step on the gas to set the choke when the engine is cold. If the choke is set too lean it might not choke or go up on fast idle if it is near 100° in the morning when you start it.

 

[toolmanmike]

Dave and Mike: This is great, I appreciate the input you guys are giving me.


(((( I have adjusted the cap to notch 4 from the front (hope you can see from the photo). The mark on the piece of tape is what I was using to keep track of several changes since I could not find the reference mark on the cap until this week because it was so far CCW past the notches and I had put my mark even past where the real mark is in the cap now at notch 4. So now it is much more lean.))))



Do you see the index mark on the cap now. That is the only mark you need. Don't confuse yourself with the tape and your mark. tear it off and get rid of it.


(((( I really think this will stop the black soot. I understand the fast idle stays until I tap the gas. Doesn't it come off fast idle one step at a time on the cam until it's fully warm?)))) Quote

The fast idle adjustment screw will make contact with a step on the cam (depending how it is adjusted) and it DOES NOT come off fast idle by itself.



(((( My problem before is that it wasn't staying on fast idle very long (that's why I adjusted it so far CCW to rich) and the engine was stalling when I had to come to a stop before it got warmed up.)))) Quote

Carbureted cars really benefit with a few minutes of warm up. They will not run like a modern fuel injected car from a cold start unless everything is adjusted exactly perfect and then you need to be a bit on the rich side to make that happen. You may have other issues that are causing the stalling depending on how you drive it and what you expect it to do when started cold.

 

[Ed Martin]

I see the index mark on the cap it looks one notch right from center. (looking at it straight on. That is rich I believe. ) Never adjust it more than 1 notch at a time. The caps always had a arrow and Rich/lean marked on it as to which way to go. Those Holleys have the fast idle cam behind the choke assembly. (the red plastic cam. it should be free and move with gravity when you step on the gas to set the choke when the engine is cold. If the choke is set too lean it might not choke or go up on fast idle if it is near 100° in the morning when you start it.

I understand and agree. I made this adjustment (to notch 4) to where I was trying to get a compromise between keeping some fast idle (rich, cap CCW) yet getting rid of the black soot (lean, cap CW). I adjusted multiple notches since I was so far off before (once I found the real index mark on the cap). So I will see hoe it goes. Thanks

 

[toolmanmike]

I understand and agree. I made this adjustment (to notch 4) to where I was trying to get a compromise between keeping some fast idle (rich, cap CCW) yet getting rid of the black soot (lean, cap CW). I adjusted multiple notches since I was so far off before (once I found the real index mark on the cap). So I will see hoe it goes. Thanks

Sounds like you are getting it dialed in. I think with a properly adjusted choke and letting it fast idle a couple minutes or so you won't have any issues.

 

[Ed Martin]

Sounds like you are getting it dialed in. I think with a properly adjusted choke and letting it fast idle a couple minutes or so you won't have any issues.

That's what I was thinking … just let it fast idle longer. BTW, for months in trying to get rid of black soot, all along I thought the problem was due to stale gas not burning completely when cold on startup since it was very hard to start and the gas in the tank was well over a year old; but it fired right up when I tried starting fluid to start. It wasn't until I filled up with fresh gas and the black soot was still there that I figured there was something else wrong.