Black smoke coming from exhaust

Tiny
DLARR
  • MEMBER
  • 1983 JEEP CJ7
  • 125,000 MILES
Thank you for your website. I have an all original vehicle (listed above) which is blowing black smoke from the exhaust. If the vehicle is idling you will not see any smoke, but when you increase the throttle it blows heavy dark smoke. What can I do with her to stop the smoke problem? Many thanks, David
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Wednesday, October 30th, 2013 AT 4:58 PM

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Tiny
JACOBANDNICKOLAS
  • EXPERT
Dave.

Black smoke indicates that the fuel mixture is too rich. Is the air filter clean? Is the choke opening fully?

Just an FIY, CJMEDVAC is the tech to give the best advice on CJ vehicles. Most likely he will pick up on this. However, if he does not, let me know about the questions I asked.

Joe
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Wednesday, October 30th, 2013 AT 5:20 PM
Tiny
CJ MEDEVAC
  • EXPERT
Let's start out with the meat and potatoes

Feel free to add anything else space is no problem.

I need to know these things:

Engine size, transmission (manual or automatic), transfer case.

Modifications that you or others have done.

Where do you sort of live? Are you emissions tested in your region?

Knowing your abilities (and engine knowledge) and tool collection, like maybe a timing light and a dwell/ tachometer (portable type). I might be able to "taylor" my rural route explanations to suit you better.

The medic
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Wednesday, October 30th, 2013 AT 7:18 PM
Tiny
DLARR
  • MEMBER
Thanks Joe and The Medic! This is my first time on this site and I am already seeing that I will enjoy the brotherhood very much. To do my best to answer the questions so you can help me more. I bought the vehicle. I found it online from a dealer in Chapin SC, but based on the paperwork I received with the CJ, the Jeep spent its life in Florida. The body and engine are original with very minor cancer spots in places around the windshield. The engine is the six cylinder and the air filter was switched out from what I can tell. It is a small rectangle filter and not the typical AMC drum filters they used back then. The vehicle is babied beyond normal. She only comes out on nice sunny days and never has her top nor doors on.

So, I have used air filter cleaner today and will oil the filter shortly. When I removed the air filter I could tell there was fuel in the pan under the filter itself. So your comment about running rich makes perfect sense. So the information I guess I need is how do I adjust the richness. Also, is there anything else I can do to improve the performance. Regarding my resources at my disposal are the basic tools (I have a huge tool collection, but tools for everything and not just mechanic tools) and a good brain to follow instructions. I am strong with vehicle wiring, but not so strong with engine moving parts. I spent a few years decades ago working in a garage and picked up some knowledge from the mechanics. I definitely do not have a timing light so hopefully we can resolve the problem without that or I will have to buy one. Oh, you also asked about the transmission and it is manual. Let me know if I missed something and also if you need pictures of anything if it will help.

Best regards to you both,
David
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Thursday, October 31st, 2013 AT 4:11 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Dave.

We are glad to help. I am going to wait for CJ to reply to you. He is the expert on CJ vehicles. If he does not get back to you, I will follow up. However, I know him and he spends time just looking for questions like this. Lol

Good luck and let me know if there is something I can do to help.

Joe
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Thursday, October 31st, 2013 AT 4:31 PM
Tiny
DLARR
  • MEMBER
Thanks again Joe! You are a good man.

All the best,
David
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Thursday, October 31st, 2013 AT 4:44 PM
Tiny
CJ MEDEVAC
  • EXPERT
I gotta know what we are starting with, Weber and Solex come in different configurations and (to me) are a bit more difficult to tune (and understand). I feel sure they are "good", tuned by a higher-tech feller than me.

You really cannot beat a bbd, simple to tune. Properly tuned, you can squeeze 16 mpgs out of it! I just had to have more (two more, as it ended up) thus I spent a lot of time and effort making my Holley work better not to mention around $800.00 for it and the intake. My friends kept telling me I could buy a lot of gas for $800.00, I just had to prove I could improve over the bbd. Along the way I tried about every "gimmick" there was to aid in it, with no improvements

I am going to shoot you two pictures. First is a "carter bbd" (original) view from front

Second is a "Weber dgev" there are other "look alike" brands

Lay your hood back on your windshield frame stand on the bumper both sides give me some full engine shots and any more you want. It is nice to have a picture of the whole vehicle, so we can see what we are blindly working on.

I am "suspecting" yours has a choke issue. It may feel like it's "holding back" as you drive?

I prefer a manual choke installation puts me "in command of when it is off or on! Also eliminates parts stick and binding (just by completely eliminating them).

I even have pictures showing how they are installed/ how they work.

So here is the other set of pictures I want from you.

Take off the air filter, leave it off, touch nothing else under there!

Vehicle is/ needs to be, cold. Actuate the gas pedal (did something click at the carburetor?) If so, it was the choke closing (like it should).

Take a picture of the topside of the carburetor!

Now drive it maybe three to five miles it should be at operating temperature by now.

Take another picture, top of the carburetor, are the choke butterflies standing 100% straight up?

Now go to the passenger side take several pictures of the choke cover and surrounding area (if need-be, I will try to explain how to adjust the choke, if indeed, it needs it).

Have you posted a question in the past?

I am over here, in Western SC. 80 Miles from chapin. Are you close?

Your turn, pictures. Anymore information?

The medic
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Thursday, October 31st, 2013 AT 9:04 PM
Tiny
CJ MEDEVAC
  • EXPERT
First picture did not make it through.

My big camera pictures have to be resized. I must have not a went small enough. Here is another picture of the missing (OEM) Carter bbd carburetor.

THE MEDIC
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Thursday, October 31st, 2013 AT 9:14 PM
Tiny
DLARR
  • MEMBER
Thanks Medic, I will take the engine pictures and send them over. I have attached two pictures I found on this computer that shows you the baby we are working on. I was concerned that the carburetor was not original, but was hoping it was just the filter that was changed.

I will get the photos you outlined in your message.

Thanks again Medic,
David
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Thursday, October 31st, 2013 AT 9:55 PM
Tiny
DLARR
  • MEMBER
Good morning Medic, I have tried two times to send over seven pictures, but it has failed both times. I will try to send two at a time and then if I get them out to you, I will rewrite everything from my original message. Too bad I did not think to copy the message on the first attempt so I would not have to keep rewriting. The first version is always better.

All the best,
David
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Friday, November 1st, 2013 AT 2:47 AM
Tiny
DLARR
  • MEMBER
Here are pictures three and four.
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Friday, November 1st, 2013 AT 2:48 AM
Tiny
DLARR
  • MEMBER
Here are pictures five, six, and seven.
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Friday, November 1st, 2013 AT 2:50 AM
Tiny
DLARR
  • MEMBER
FYI, this is the second time for this message as well. I tried to send the remaining three pictures, but it did not go through. So attached now are five and six. I will then write up my original message and attach the last picture I took.
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Friday, November 1st, 2013 AT 2:52 AM
Tiny
DLARR
  • MEMBER
This is my third attempt to get you the remaining photos. I will try sending one at a time now.
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Friday, November 1st, 2013 AT 2:53 AM
Tiny
DLARR
  • MEMBER
Sorry for all the messages. If we do more pictures, maybe we should go with our email addresses. This is the fifth time I am trying to get the last three pictures over to you. I closed the page and opened it again to see if now it will go through.

Cheers,
David
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Friday, November 1st, 2013 AT 2:56 AM
Tiny
DLARR
  • MEMBER
Medic, I cannot get the last pictures over to you. Can we switch to email? What is the best way to communicate this information if you agree? I have written a detailed message, but I attached the pictures and it was lost because I do not see it posted. I am not even sure if this one will go through with out any pictures attached. We shall see. If it goes through I will rewrite the message, but I need to find another way to send over the pictures.

All the best,
David
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Friday, November 1st, 2013 AT 2:59 AM
Tiny
DLARR
  • MEMBER
Sorry buddy, I did not know there was a page two. I thought it would just keep going down on the same page.
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Friday, November 1st, 2013 AT 3:00 AM
Tiny
DLARR
  • MEMBER
I am not near you, but I did live in Charleston for four years just over a decade ago. I have been living in NJ for the past eleven years. I moved around because of my employer at the time moved me around the country. So, as much as I wish I still lived in SC, I do not see any chance at this time to move back down there.

So, talking about the carburetor again, yes my baby seem to hold back when I step on the gas. I noticed that if I tried to put the pedal to the metal it behaved like it was getting flooded. Also, when I am in fifth gear, I lose power so I find myself down shifting to fourth to handle any kind of incline or to pass someone.

I am assuming at this point that when I take her out for the three to five mile drive (I hope that the rain stops today long enough to get this done when the sun comes up) that I must have the air filter in position and then carefully remove it to get the second shot of the carburetor. Does the CJ need to be running when I take the second shot or will the flap stay in whatever position it is in even if the CJ is off? I hope you see this message this morning so I can try to get everything done today so you have the information to give me the advice to fix my baby. I am psyched to help get my baby running smoothly and efficiently again.

I cannot thank you enough. I never post any questions on the internet before now, so I am blessed that I found you and Joe in my first experience. You have inspired me to find a way to pay it forward, but I am not sure yet how I can be of assistance for others. I definitely am good with any wiring questions for vehicles and boats (basically DC, and not AC. AC has a way of always biting me when I am working with it).

I look forward to hearing from you. Thanks again for everything.

All the best
David
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Friday, November 1st, 2013 AT 3:30 AM
Tiny
CJ MEDEVAC
  • EXPERT
You do have a Weber dgev "progressive carburetor", meaningduring normal driving you will be operating on only one barrel

When you really stick your foot into it your main barrel (the normal one) will be fully opened and the seconnd barrel will begin to open (and progressively) open more and more as you push the pedal deeper

As I said before I gave up on "tweaking" the Weber I had, I do kind of understand its theory for some reason he and I could not get to together on how "I" wanted him to work! The advertisements promised 20% better power and mp'gs than the OEM bbd. I never was able to get a.01% improvement, with my many tweaking's, I went into the "negative" on mpg's, than the 16, I got with the OEM bbd.

Since then, and with my Holley, I have picked up some tips that have helped the Holley they might could of helped with the Weber. Water under the bridge for me.

Let's see if you have a choke problem first I can talk you through a "fix" for that.

Maybe your carburetor will suit you better, and you will stick it up with the Weber.

If you want to go back to OEM I can help you through that whole deal too, maybe save you some money obtaining one also.

Your turn.

The medic
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Friday, November 1st, 2013 AT 5:09 PM
Tiny
DLARR
  • MEMBER
Medic, sorry the rain continued today and messed up my plans, but tomorrow is supposed to be great and 70 degrees. I think we should try to tweak the carburetor once we know what it is doing, but in the back of my mind I am thinking it might be best to change carburetors and put on one you recommend.

Attached a picture of one of my other Jeeps, my work-horse.

Thanks
David
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Friday, November 1st, 2013 AT 5:35 PM
Tiny
CJ MEDEVAC
  • EXPERT
Your Weber may work just fine with a "possible" choke adjustment and maybe tweaking the mixture screw (I will show you the techniques. So do no monkey with stuff yet! Others may have monkeyed with it earlier)

Let me know when you are ready. I am always here, ready to jump! As long as you will remain on this same thread.

THE MEDIC
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Friday, November 1st, 2013 AT 8:25 PM

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