Fuel line adapter

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maxtwms

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I'm replacing my aluminum fuel line with a braided steel line. Braided line has AN-9 (9/16) internal thread fittings on both ends... I need to adapt it to what I believe is a 5/8 internal thread for the carb and fuel pump. I went to both advance and O'Reilly and neither had anything. Is this a typical install? Am I looking for the wrong thing? Holley 4175 and stock looking fuel pump. Sorry if already posted somewhere else..

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chengny

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I'm replacing my aluminum fuel line with a braided steel line. Braided line has AN-9 (9/16) internal thread fittings on both ends... I need to adapt it to what I believe is a 5/8 internal thread for the carb and fuel pump. I went to both advance and O'Reilly and neither had anything. Is this a typical install? Am I looking for the wrong thing? Holley 4175 and stock looking fuel pump. Sorry if already posted somewhere else..

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9AN? I didn't think that size existed. I am probably wrong, but I thought the only odd number sizes were 3,5 & 7. After 7 they were all even numbered sizes (8,10,12...).

On the pump outlet, you are right - the thread size is 5/8" - 18. That is also the size of the threads on the inlet side of a Quadrajet inlet adapter fitting. This probably doesn't matter to you but, the threads that screw into the carburetor body are 1" -20.

You probably want something like this - but with the correct AN size:
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Adapter fitting allows use of high performance racing fuel hoses and fittings. Adapter fitting has a male 5/8"-18 flared end that screws into the OEM inlet fitting. Number 6 AN male fitting is flared to accept standard #6 AN female hose fittings. Great for applications where custom steel braided fuel line is used.

Fits factory and aftermarket mechanical fuel pumps with 5/8"-18 thread connections.

https://quadrajetparts.com/fuel-inlet-adapter-fitting-p-369.html?osCsid=6udduik2fv2j3r5b5abmt0kku2
 

maxtwms

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I think I ended up finding the correct parts?... The hose is -9AN OD with a -6AN ID. It's very strange because the description says it has -6AN fittings but the ID of those threads are 9/16 (-9AN). So I ordered these -6AN to 9/16 fittings. Honestly have no idea if these are going to work... Not sure what the AN descriptions mean entirely
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I don't know about your specific carb, but most fuel pumps are NPT or threaded for a tube nut with an inverted flare.
 

chengny

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I think I ended up finding the correct parts?... The hose is -9AN OD with a -6AN ID. It's very strange because the description says it has -6AN fittings but the ID of those threads are 9/16 (-9AN). So I ordered these -6AN to 9/16 fittings. Honestly have no idea if these are going to work... Not sure what the AN descriptions mean entirely

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As you probably know, AN stands for Army/Navy and dash (-) number represents diameter in 1/16th's of an inch. IOW, what they are calling -9AN hose, is simply 9/16" OD hose. The hose OD/ID isn't related to the size of the fittings that are swaged to it's ends - within reason.

You should be alright on this. Disregard the -9AN hose OD designation - that is usually only critical (and used) in specs for marine/military/aircraft applications. It is important when a hose or tube passes through a watertight/gas tight bulkhead. In those cases it must be able to form a tight seal with the gland through which it passes.

At it's most basic, you are working with 9/16" OD hose and -6AN fittings for the ends. But one thing that might be a problem: From what I read in the description of the hose you are buying, it appears that you are getting 12' of bulk hose and an assortment of fittings. The fittings will have to be swaged to the hose ends before it is usable. Any hydraulic supply shop should be able to help you - also I believe most NAPA stores have good equipment for that.

Check out the working/burst pressure and temperature ratings in the product description - you are buying the Cadillac of fuel lines my friend.
 

Blue Ox

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I think you mean ID when you're referring to the dash number. At least if you're referring to the -6. Like chegny said, I've never heard of -9, but if it existed it would still refer to ID. Is the 9 they're referring to the thread size? As in 9/16"-24 diameter and pitch.

I've never hear of OD referred to as an AN number. I think it would only cause confusion and problems.
 
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Dutch Rutter

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When I did mine I used -6AN fittings and line. I ended up getting the line as a kit. but the fitting were kinda tough to locate as no local part stores or hardware stores could find me anything. They pretty much looked at me like i was crazy. I ended up ordering everything online.

For my application I used one of these to the pump http://www.jegs.com/webapp/wcs/stor...&submodel=&engine=&Nrpp=&No=&persistYmm=false

and a few of these 45s https://www.summitracing.com/parts/vpe-10772 because I was using a flexible line I needed the 45 to move the line away from important and hot things.

I think a -9AN is pretty large for a pump to carb fuel line. What I was reading when I was doing this said -6AN.
 

maxtwms

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I think you mean ID when you're referring to the dash number. At least if you're referring to the -6. Like chegny said, I've never heard of -9, but if it existed it would still refer to ID. Is the 9 they're referring to the thread size? As in 9/16"-24 diameter and pitch.

I've never hear of OD referred to as an AN number. I think it would only cause confusion and problems.
Yes that's how they referred to the OD. That's why it took me a while to find what that spec actually meant. I found that I need a -6AN fitting for the AN hose fitting I have now (OD HOSE for a -6AN is apparently assumed to be 9/16 which is where the -9AN came from and is the typical ID thread size for the -6AN) and a 5/8 fitting for the pump side. So -6AN to 5/8. Hope that was confusing enough. I ordered them this morning.

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maxtwms

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9AN? I didn't think that size existed. I am probably wrong, but I thought the only odd number sizes were 3,5 & 7. After 7 they were all even numbered sizes (8,10,12...).

On the pump outlet, you are right - the thread size is 5/8" - 18. That is also the size of the threads on the inlet side of a Quadrajet inlet adapter fitting. This probably doesn't matter to you but, the threads that screw into the carburetor body are 1" -20.

You probably want something like this - but with the correct AN size:
You must be registered for see images attach
You must be registered for see images attach



Adapter fitting allows use of high performance racing fuel hoses and fittings. Adapter fitting has a male 5/8"-18 flared end that screws into the OEM inlet fitting. Number 6 AN male fitting is flared to accept standard #6 AN female hose fittings. Great for applications where custom steel braided fuel line is used.

Fits factory and aftermarket mechanical fuel pumps with 5/8"-18 thread connections.

https://quadrajetparts.com/fuel-inlet-adapter-fitting-p-369.html?osCsid=6udduik2fv2j3r5b5abmt0kku2
This is the correct answer for exact part. Thanks for the help.

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highdesertrange

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first off the fuel pump and carb have inverted flare fittings. so you need adapters from inverted flare to AN. the steel tubing you are replacing is 3/8's. which is -6 AN. OD is irrelevant. highdesertranger
 

maxtwms

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first off the fuel pump and carb have inverted flare fittings. so you need adapters from inverted flare to AN. the steel tubing you are replacing is 3/8's. which is -6 AN. OD is irrelevant. highdesertranger
This is what I ordered.
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maxtwms

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I realized I was playing with a softer metal but I have dissimilar metals regardless so I went with the cheaper

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