71 350 Carb Question
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Melting Slicks
Joined: Jul 2005
Posts: 3,389
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From: Norfolk Virginia
71 350 Carb Question
Carb #7041212 DL I put a kit in it but I have no real adjustment withe air/fuel screws. I turn both of them all the way in and it has no real effect, same thing if I turn them out. the motor idles pretty rough too. I put a vacuum guage on it and watched it as I adjusted the mixture screws, I saw no real change there either. Is this a bad throttle body?
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Sep 6, 2021, 07:23 PM
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From: At my Bar drinking and wrenching in Lafayette Colorado
Cliff and I have both been accused of being, "harsh," "intolerant," and "ridiculous" regarding our opinions and comments about the commercially "remanufactured" carbs. Unfortunately, we speak the truth, and the truth is brutal when it comes to junk carbs.
Lars
V8FastCars@msn.com
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
It's a plugged idle feed circuit in the carb, improper assembly, incorrect gaskets, or an incorrect setup. You're idling on the main discharge circuit.
Lars
Lars
Thread Starter
Melting Slicks
Joined: Jul 2005
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From: Norfolk Virginia
Thanks for that Lars. I took it off and ran some wires, cleaner and air through it and that helped it a lot, at least it will idle now.
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Check the gasket used between the main casting and baseplate. Unless you use an application specific kit they typically supply several choices and there was a change made in those gaskets and using the wrong one blocks idle bypass air. The idle tubes really need to be pulled to effectively clean them. Running wire thru them may open them up but will not remove the 50 years of "varnish" built up in the tips from countless drying up cycles. I sell the most complete and correct Quadrajet rebuild kits in this industry and only supply the correct gaskets and parts used in the carb by part number.......Cliff
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 3,389
Likes: 83
From: Norfolk Virginia
Check the gasket used between the main casting and baseplate. Unless you use an application specific kit they typically supply several choices and there was a change made in those gaskets and using the wrong one blocks idle bypass air. The idle tubes really need to be pulled to effectively clean them. Running wire thru them may open them up but will not remove the 50 years of "varnish" built up in the tips from countless drying up cycles. I sell the most complete and correct Quadrajet rebuild kits in this industry and only supply the correct gaskets and parts used in the carb by part number.......Cliff
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Anything commercially "remanufactured" is going to be a pile of bovine excrement so good luck going in that direction. I will not touch them here and when they incidentally show up I very carefully close the box and send them back to the owner.
Manual cleaning is required for idle tubes, nothing else will remove the "varnish" built up in them from drying up cycles over nearly half a Century.......
Manual cleaning is required for idle tubes, nothing else will remove the "varnish" built up in them from drying up cycles over nearly half a Century.......
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Cliff and I have both been accused of being, "harsh," "intolerant," and "ridiculous" regarding our opinions and comments about the commercially "remanufactured" carbs. Unfortunately, we speak the truth, and the truth is brutal when it comes to junk carbs.
Lars
V8FastCars@msn.com
Last edited by lars; Sep 6, 2021 at 07:29 PM.
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 3,389
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From: Norfolk Virginia
That's a really bad idea, and a complete waste of time and money. The commercially rebuilt carbs are complete junk, and are best used to practice your hook shots into the garbage can in your garage. Neither Cliff nor I will touch those things. E-mail me for a copy of my paper "Commercially Rebuilt Q-Jet Problems" if you'd like to see a 3-page list of just a few of the things that will be wrong with that carb. Fix your original carb properly (soaking it in a "dip can" is not going to clean out the idle passages) and scrap that "remanufactured" thing.
Cliff and I have both been accused of being, "harsh," "intolerant," and "ridiculous" regarding our opinions and comments about the commercially "remanufactured" carbs. Unfortunately, we speak the truth, and the truth is brutal when it comes to junk carbs.
Lars
V8FastCars@msn.com
Cliff and I have both been accused of being, "harsh," "intolerant," and "ridiculous" regarding our opinions and comments about the commercially "remanufactured" carbs. Unfortunately, we speak the truth, and the truth is brutal when it comes to junk carbs.
Lars
V8FastCars@msn.com
I have since become just like him 
So what do you recommend I use to clean out the idle passages? And where exactly are they, pics? I know very little about carburetors
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Joined: Jun 2010
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Several methods can be used to clean idle tubes. They can be difficult to clean effectively as they are driven into the main casting and the small tip is not accessible.
I prefer to pull them and manual clean with a precision drill bit in a pin vise......
I prefer to pull them and manual clean with a precision drill bit in a pin vise......
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 3,389
Likes: 83
From: Norfolk Virginia
That's a really bad idea, and a complete waste of time and money. The commercially rebuilt carbs are complete junk, and are best used to practice your hook shots into the garbage can in your garage. Neither Cliff nor I will touch those things. E-mail me for a copy of my paper "Commercially Rebuilt Q-Jet Problems" if you'd like to see a 3-page list of just a few of the things that will be wrong with that carb. Fix your original carb properly (soaking it in a "dip can" is not going to clean out the idle passages) and scrap that "remanufactured" thing.
Cliff and I have both been accused of being, "harsh," "intolerant," and "ridiculous" regarding our opinions and comments about the commercially "remanufactured" carbs. Unfortunately, we speak the truth, and the truth is brutal when it comes to junk carbs.
Lars
V8FastCars@msn.com
Cliff and I have both been accused of being, "harsh," "intolerant," and "ridiculous" regarding our opinions and comments about the commercially "remanufactured" carbs. Unfortunately, we speak the truth, and the truth is brutal when it comes to junk carbs.
Lars
V8FastCars@msn.com
I'm pretty well over it and I'm wondering if you would take a stab at it? If so let me know what I need to do.
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
Had a 1976 L-82, 4-sp
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The two best QJ gurus on the planet here in a thread offering expert advice to a forum member(s) for free. Priceless!!!
Thread Starter
Melting Slicks
Joined: Jul 2005
Posts: 3,389
Likes: 83
From: Norfolk Virginia