Cantedvalve 128 Report post Posted November 27, 2018 Pump to carb hard line isn’t sealing at all. When the engine runs, it leaks. It is a new stainless steel line, but a used pump. Pump had an inverted flare to AN fitting on it before that gave no issues. I’m wondering if it isn’t the fuel line itself. I’ve read that double flared SS is not a good idea... which is what this is. Maybe cut off the double flare and put on a single? I don’t want to go back to braided line. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted November 27, 2018 exactly where is it leaking? double inverted flare on stainless is fine . i have used those lines a bazillion times but they sometimes need to be tightened then loosened slightly then tightened etc several times before they seat. grease on the threads and sealing surfaces also helps during this process. it sometimes helps to use a special "conical" sealing washer on them. Quote Share this post Link to post Share on other sites
Cantedvalve 128 Report post Posted November 28, 2018 Fixed. I tool the line off, annealed the flare (got it glowing cherry red and let it air cool), and then did the triple torque technique you outlined. I only ran the engine for a minute, but with RPM, and no leak. That is also how I did my stainless brake likes... annealed after flaring. Let’s hope it stays that way Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted November 28, 2018 13 minutes ago, Cantedvalve said: Fixed. I tool the line off, annealed the flare (got it glowing cherry red and let it air cool), and then did the triple torque technique you outlined. I only ran the engine for a minute, but with RPM, and no leak. That is also how I did my stainless brake likes... annealed after flaring. Let’s hope it stays that way that's a good trick as well. i have had to tighten the fk out of some of those sob's to get them to stop leaking. Quote Share this post Link to post Share on other sites
Her69fastback 3 Report post Posted November 28, 2018 If I’m not mistaken AN fittings take a 37 degree flare . That maybe why it’s not sealing Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted November 28, 2018 Yes, AN is 37 degrees and seal much better with less torque on the fitting than inverted flare which is 45 degrees. I fought inverted flare fittings on my fuel lines for years. They would seal fine, then will not seal the next time a fitting was disconnected and reconnected. At least so far, no more leaking issues since switching to AN fittings. Quote Share this post Link to post Share on other sites
Cantedvalve 128 Report post Posted November 28, 2018 I dunno. It is the standard fitting on the fuel pump. I am guessing inverted flare? Quote Share this post Link to post Share on other sites
69volunteer 84 Report post Posted November 28, 2018 I believe you discarded the AN fitting an bra 3 hours ago, Her69fastback said: If I’m not mistaken AN fittings take a 37 degree flare . That maybe why it’s not sealing I believe you discarded the AN and braided line and going with 'factory'. Barnett--i like those fittings. Do you have a source? Quote Share this post Link to post Share on other sites
JayEstes 172 Report post Posted December 1, 2018 Yes, those copper conical washers are "flare savers". They are used in AN fitttings. I don't have much experience using them, but they might make a good solution for sealing stainless lines. You have to keep in mind that the male side of these things is BRASS (e.g brake distribution block), so when you just tighten the F out of them, you can damage the brass parts (it's not cheap to get a new one either). This is one of the most commonly reporting problems with stainless lines is the double flares don't seal well (stainless is stronger & less ductile). I think the flare saver is probably the best idea. It's softer than brass, and will conform to both the line and the mounting surface without damaging either. For me, I'm sticking with the softer steel lines that seal more easily. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted December 1, 2018 26 minutes ago, JayEstes said: Yes, those copper conical washers are "flare savers". They are used in AN fitttings. I don't have much experience using them, but they might make a good solution for sealing stainless lines. You have to keep in mind that the male side of these things is BRASS (e.g brake distribution block), so when you just tighten the F out of them, you can damage the brass parts (it's not cheap to get a new one either). This is one of the most commonly reporting problems with stainless lines is the double flares don't seal well (stainless is stronger & less ductile). I think the flare saver is probably the best idea. It's softer than brass, and will conform to both the line and the mounting surface without damaging either. For me, I'm sticking with the softer steel lines that seal more easily. Good point and I meant that i had to tighten the f out of them even when using the washer. I didn't do that without the washer. 1 JayEstes reacted to this Quote Share this post Link to post Share on other sites
Mike65 475 Report post Posted December 2, 2018 I will be using NiCopp line for my fuel & return lines. 2 mwye0627 and JayEstes reacted to this Quote Share this post Link to post Share on other sites
JayEstes 172 Report post Posted December 3, 2018 12 hours ago, Mike65 said: I will be using NiCopp line for my fuel & return lines. My buddy used that on his 55 packard and that stuff is fantastic! For fuel- quite a bit better than a steel line. Quote Share this post Link to post Share on other sites