I have 1980 d-150 truck, with an '82 /6 motor that I recently upgraded with a 2 bbl intake and carb. The carb is a BBD I picked up from ebay, that supposedly was rebuilt. It looked clean when received anyway.

I can't get the idle below 1200 rpm w/0 it stalling. It will also oscillate more or less depending on where the idle set screws are. Worse case it'll rev to say 1500 then back down to 800 and repeat. When it gets to the low rpms a whistling is heard, but I can't find the leak. Any ideas what causes the oscillating? The carb doesn't have any feedback solenoid, its a bare bones setup, and all the emissions components are out of the engine except the PCV valve.

Next question. I took the egr valve off the single bbl manifold and mounted it to the 2 bbl manifold with a new gasket. The valve has a cap on the vacuum port. Is this enough to block off the egr port? Is the 1 bbl egr port(s) different than the 2 bbl manifold?

Down South, they call such an item a "pig in a poke". A "poke" is a paper grocery sack, so the expression basically means that you don't know what kind of trouble and strife you're taking on.
Sounds like a pretty severe vacuum leak, or an exhaust leak into the intake tract. Does the engine rev OK and run acceptably under load, and just have an idle problem? Or does it run poorly at any speed and any load?
It is unless the EGR valve itself is stuck partway open (which would've caused running problems with the 1bbl).
No.

Carburetor operation and repair manuals (and some training movies) are posted here for free download.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I'm not sure if it's a pig, but I feel like the super six "upgrade" has put me in a poke.
I can't get the engine to run well enough to try and put a load on it. I've been setting the two idle screws at 2.25 turns out to begin with. I discovered yesterday that one turn out seems alot better, but then my battery died and I couldn't go any further.
Will do a more thorough search for vacuum leaks.
It ran fine with the one bbl. The engine wasn't broke so I broke it!
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I've been reading the BBD online manual...thanks.

my only advice here is to also double check your head to manifold nuts. after i did the super six, the gasket must have crushed a bit and caused mine to loosen up. didnt have so much as a hunting problem as the car just flat wouldnt idle in gear

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1975 Plymouth Duster,225/6 2bbl. and duels, 904, 7 1/4
1986 Dodge Charger Shelby, 2.2 Turbo I, A525

according to the factory manual most vacuum leaks will occur where the carb mounts to the intake manifold.

if you know you have sealed the carb at the intake manifold, another place I found a leak was on the carb intself. There are screws that sandwhich the gaskets on a BBD. They may be loose. Screw them down. Dan also pointed out on some BBDs there are also screws that tighten the carb together upward. which means you"ll have to pull the carb off to access them. May be as simple as that. it was for me.


One thing i learned in the music world. Check your simple things like the cable and the inputs before you assume its your guitar or an amp.

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isaiah6:8
www.kenithomas.com

H'mmm. I'm not sure I agree. That might've been so when the cars were relatively young, but now they're old, there're all kinds of places for vacuum to escape.
Good advice, but don't hamfist it. If you really reef on them, you'll damage the carburetor.
All BBDs, actually.

Also good advice!

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Well I made major progress over the weekend. Turned out the intake manifold was leaking big time. So I took the assembly off again(about the third time now...with a truck its a real pain in the back!) and kinda cheated... I had and extra manifold gasket made by Fel-Pro and put that over the Aussie gasket that was leaking. So there was two gaskets squashed together. It worked...the engine fired up and initially I didn't' think it had started because it was much quieter. I sprayed "Sea Foam" around the gaskets and carb and did not find any leaks. I know this is a band-aid, but for now I'm leaving it with the two gaskets.


I was able to take the truck for a ride and the difference in performance was very noticeable. But I still have an idle problem. Now I can't get the idle below 1100 rpm without messing with the timing and when I change the timing the truck loses power. The set screw for the accelerator on the carb is all the way out and it still idles at 1100 rpm. The two idle set screws are approximately 2.25 turns out. The timing is roughly 18deg BTDC. The engine runs rock steady at 1100 rpm, but of course sucking down alot of gas at that speed.

Any comments are very appreciated. Thanks.

A leak with a thick, soft, compressible gasket like the Australian or Remflex one means you probably have a (very) warped manifold(s).

Sounds like you still have carb problems, tho.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Do the intake manifolds warp? The exhaust manifold is a brand new Mopar manifold and it seemed good.

I don't know the history of the intake, I got it off ebay. The only odd thing about it was the thickness of the ears between where the mounting washers sit and the head surface. The ears were about 1/8" thinner than the exhaust manifold ears. I ground down and carefully filed the exhaust ears so they were about .020-.030"thinner than the intake ears. I also had to file out the hot box holes to make them larger.

Any idea why this intake manifold had the thinner ears?

They certainly can.
Toss that in the "poke" with the piggy carburetor! Is it an iron or aluminum intake?
Errr...why did you do that?
That's the way it's supposed to be.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Are you sure? They don’t make those anymore. The reproduction manifolds can take some work to bolt together straight. Originals may not be much better. My engine has the original head and original 1 barrel intake and the ports don’t line up. You really have to check everything.

If you haven’t already, you can read all about manifold mounting HERE.

Danny

I got it off ebay... , but it came in a Mopar box, it was still in a sealed plastic bag and the casting has Chrysler markings on it. Compared to the one i took off my truck that clearly said "Made in China" and had no Chrysler castings/marks. It still had a coating of some kind of grease and the heat riser mechanism was in perfect shape.

Its'a cast iron intake.

The reason I ground down the exhaust ears was because I could not see how the intake would seal if the exhaust ears were an 1/8" higher(or more) than the intake ears. And to back this up, the instructions from the "Fel-Pro" gasket state that the intake ears are purposely slightly thicker than the exhaust ears so the washers will apply slightly more pressure to the intake ears. I didn't read the gasket instructions until after i had ground away so I felt a little better after reading that. I also looked at as many intake/exhaust manifold pictures on the web that I could find. I didn't see any where the exhaust ears were much higher than the intake. Anyway...it's done now...I'm not going to buy another manifold in the near future and besides what could possibly go wrong

Just for grins here is some pictures of the manifolds before I ground on the exhaust. This is the first time I've tried to use "Picassa" from Google so sorry if it doesn't work. Go to http://picasaweb.google.com/maierscott

The pictures don't really show how different the exhaust flanges(ears) were from the intake, but you can sort of see it.

It works now...just click on the above link for the pictures