This is the carburetor from the 1979 Lebaron that came with my Super Six setup. Can anyone identify the exact model based on the digits molded into the body? The bowl is marked O-2543. It has a sticker from a rebuild shop with dot-matrix printed digits that are hard to read (I could look closer if the numbers would mean anything to anyone).

The biggest problem I've found so far is that the throttle is completely seized and the plates are crusted with rust. PB Blaster hasn't worked yet, but I'm still holding out hope. I assume I could remove the plates, punch out the shaft, and rebush? Also, a handful of white flaky powder fell out when I opened up the bowl (photo below). I assume this doesn't indicate anything particular about the carburetor. The choke butterfly plate is rusty too, but it moves freely. The area around the metering rods seems OK at first glance.

Is there any hope, or would any sane person order a rebuilt one and send this in as a core?

Also, is it normal to have two bolts and two studs connecting the carb to the intake manifold? Or was that someone's make-do job?

Bang for the buck wise your best bet would be to look in the classified ad section here and see if the guy who had the NOS BBD 6537s for sale has any left. I bought 2, used 1 so far and what a difference.
You will have to either swap throttle butterflies or fill in the 1/8" holes in them on that carb and there are minimal vacuum ports on it but for a fresh engine it would be the best way to go.
A parts store bought rebuilt is usually a crap shoot, and please don't stoop to buying one of those chinese repops on ebay for under$100.
Someone with a 1979 factory manual would be able to narrow down the real carb number in a hurry, as that number you show starting with an "0" is a casting number not the carb number. For a given year and engine there should be only 2-3 specific carbs used and you can probably scratch off the Cali specified one right off the bat unless. You somehow think it came from there. There may also be a "hi-alt" spec one that you can eliminate as well. The remaining choice would be what you have.
Now mind you, 2 things/
As I remember you saying that this setup as found in the trunk, I've found quite the mishmash of parts in the trunk of cars in the yard,it may have been off of something else that was parked nearby at some point.
If it is a reman does not mean that they put an identical carb on there then either.
And also being that your car isn't a 79 there may be ports or plungers that wouldn't be needed for your year, some of which can simply be plugged off.

Oh yeah on that one listed here it was a truck application from like 1976ish 318 truck with "heavy duty" emissions which back then meant "minimal" emission control, wouldn't even have had egr on it. "K.I.S.S." if it ain't there it can't screw up for you. Keep it simple.

If it were me, I would use it as a core or just find a different carb. That doesn't appear to be a slant six specific carb and it has been "remanufactured" which means the protective coatings were probably stripped off of the various parts that get them.

If you are interested in saving that carb, I would start by soaking it in a carb cleaner "dip tank" overnight and then immerse it in evaporust for a few days. Once that is done, I would run it through an ultrasonic cleaner.

In the long run, just getting a different carb is probably the best choice.

Like THIS ONE that appears to be a true Super Six carb.

_________________
Casually looking for a Clifford hyperpak intake for cheap.

while it does have the "bent" PCV hose nipple if it is a 1974 spec carb, it wouldnt be a super 6 carb because they had not yet come out with teh super 6 pkg in the US on cars as of then....
shouldnt be hard to find out what year the 8016S was used..... though the seller says there was no tag, was just written somewhere that that is what this carb is.
not as bad as yours looks (though that carb Reed showed the link to wasn't dismantled yet either) there is what appears to be quite a bit of oxidation on the base plate.
truth is they built a gazillion BBD's that were all "almost" the same as any other.... many even with same count of vacuum nipples and other things that differentiate one from another.... there is far from "only one certain exact carb number" that will fit and function on your car.
I have had to piece them together before to get 1 good carb. Not just talking about BBD's either... Holley 1945s, Carter TQ's, even lawnmower carbs. but in some cases tehre is simply no hope of success, too far gone for even an established shop to "bench" rebuild. sometimes it does not matter what you do to them they are doomed.
Without being able to drill out ball plugs and such for access to EVERY nook and cranny, rebushing shafts, etc sometimes there is just no hope for a given carb.... without being able to access some of these remote passages you can't always get all the trash out of one. and you'd need a mill and a dang good vise to hold the casting in just the right angle at that.... Don't necessarily buy the 1st one you see..... I actually have 3 BBD's (all late 70s 318 versions) on the shelf here collecting dust that I believe I will wind up with at least 2 good carbs out of, when all is said and done. I have kits and new floats for them as well, but since I bought those 2 NOS ones I havent needed these other ones. I have a 318 in a Fury that needs to be de-lean burned, plans are to "4 bbl" that engine in the process, these BBD's I have are currently my "plan B" or maybe "intermediate step" if I de- Lean burn before I get a chance to manifold-swap it.....
Originally I was gonna try and build them up for both my son's slant and mine as well, but I found the guy with the NOS ones and bought them just out of "laziness" at the time.

Just to be clear, when you saw parts in the trunk, that was the trunk of my Dart. The whole setup was still installed in the Lebaron until I had it pulled. That said, clearly it's not the original 1979 carburetor. But it does have the correct choke linkage and no holes in the throttle plates.

Reed, what about the eBay carb makes you say it's a Super Six carb? It's labeled as a fit for a 1974 318. And isn't it set up for the V8 choke linkage?

Regarding using an older or truck BBD, I'd like to have an EGR control port if I could reasonably hope to get EGR working right. But then it's not clear to me how much benefit it really offers. I want a clean-running engine within reason, but if emissions were my top priority, I wouldn't be driving a 46 year old car.

I found this Chinese copy of a 318 BBD. It wouldn't be the first Chinese part on my car, thought it would be the most prominent. https://www.amazon.com/Madlife-Carburet ... 59&sr=8-23

I guess I'll keep trying to clean up this junk carb and see what I can get out of it.

The biggest giveaway about being a"slant 6 carb" in the one that Reed posted to me is the pcv port that bends like a pigtail on the carb base. On the "318 choke" or "slant 6 choke" there's a difference in the link that the choke connects to between them. There are workarounds posted here, seems not all that long ago but they may just have been linked to bring them back to the top. In my case I found that exact piece on ebay by itself, only 1, 3/8 nut (wrench size) nut needed to remove to swap out.

Yeah I know about seeing it in your trunk but I thought that it was found in the trunk of a car in the yard too.

On the Chinese carb not being the only chinese part that would be on the car I still don't trust them enough to get one. A good carb is one of the most important things on that engine. Not something I'd want to have doubts in my head over.
I've tried a couple on mowers and garden tractors and was not impressed, sure wouldn't want one on something I have to depend on to get me past my own property line. Not yet anyway. Let's let others be our guinea pigs for a while yet and see how they work out.
On the small engine side there are those who swear by the Chinese carbs, but the sellers of them seem endless, idk if they all come from the same assembly line and distributed by millions or if there are certain ones that are better than others. They all look identical so it's hard to say. I would have the same quality based question about one for a car.

oh yeah I think Reed wrote the article in that section (articles) about a true "Super 6" carb....

After no joy freeing the seized throttle shaft after several days of PB Blaster, I slathered naval jelly all over the throttle body. It removed a lot of visible rust but it didn't free up the shaft. Next I boiled the throttle body in a roughly 50/50 mix of "30% vinegar" (that's 30% acetic acid) and water, with some Simple Green concentrate for good measure. I used a disposable turkey tray on a gas grill. After about 15-20 minutes of boiling, I picked up the (still hot and wet) throttle body with channel-lock pliers and used another pair of pliers to try to rotate the shaft. It moved just a bit, so I wiggled it back and forth, put it back in the boiling vinegar water, and smiled as a puff of reddish brown billowed out. After a few rounds of this (maybe 30-45 minutes total of boiling), the shaft rotated freely!

I then rinsed the throttle body in fresh water with baking soda to neutralize the acid, and flushed with acetone to dry it. What I should have done is immediately spray with WD-40 or something to prevent surface rust from forming immediately. But I didn't, and surface rust formed within a half hour. However, the shaft still moves freely.

In the closed position, the shaft has zero play. In the wide-open position it has about 0.030" of end-to-end play and about 0.011-0.012" of side-to-side wiggle. I'm not sure if that's enough to cause the vacuum leak problem?

After naval jelly application:


Boiling (the vinegar water was deeper when I started):


The photo I used to measure the side-to-side gap in the shaft:


The payoff:

Nice work! Any visible/measureable play in the shaft is too much. I hope the mixture crews were removed when you did the boiling treatment.

_________________
Casually looking for a Clifford hyperpak intake for cheap.

Sadly I didn't think to remove the mixture screws first. In fact they were quite difficult to turn even after the boiling process. But I saved my vinegar mix and I have plenty of propane...

I guess the next project is to install a new throttle shaft bushing. I measured the shaft diameter at 0.30" but apparently the BBD spec is 5/16".

Any tips on drilling the hole straight for the new bushing?

Know anyone with a mill? May have to make up/fabricate bushings too.
You'll have to file off the exposed threads holding the butterflies in as they are probably staked to prevent backing out while on the car.

https://www.ebay.com/itm/5-16-Throttle- ... 1438.l2649

_________________
Casually looking for a Clifford hyperpak intake for cheap.

The best penetrating oil-snake oil-wizzard in a can- I have ever encountered is called "Free All" and I get it locally at an supply house, granger may carry it, tho I am sure amazon would have it as well.. Never seen it at an auto parts store.

It is about $7 for the standard size aerosol can. It smells strongly when working and I don't like using it indoors, as it will take your breath away, but it will loosen rusted nuts like nothing I have ever seen... I don't bother with WD 40 or PB blaster any more as they are a waste of money for the results they deliver.

I like your idea of boiling the carb. Heat is a good solvent enhancer. . . maybe boiling one in the molasses-water style rust remover would loosen corrosion? I have not got a carb with any white powder to try the molasses trick on, but someday I will get to see if it works.

I ordered the bushing kit from eBay.

I also took out the throttle plates. Somewhat alarmingly, the screws weren't actually staked, but they were tight all the way out. I don't know if that was thread sealer or they are just made tight like valve adjustment screws. One actually broke off about halfway out and I had to drill it out.

When I got the shaft out, I discovered that there isn't much room for a new bushing in the throttle body (I measured the wall thickness at 0.067" at the thinnest point). I'm not sure if this is going to work...