connect 10mm tube to -6AN?

I need to connect a 10mm steel tube to a hose assembly with a -6AN end. now 10mm is real close to 3/8" so I am tempted to just slide on a -6AN tube nut, try to flare to 37 degrees using a 3/8" flare tool, throw on a union, et voila. However, the engineer in me says that is wrong, wrong, wrong and that I should use an ISO flare and an adapter to -6AN. The problem is that I can't seem to find either tube nuts for the ISO flare or the adapter to -6AN. Any ideas?

Application is a fuel line for a Porsche 944. The 10mm tube is one solid piece all the way back to the fuel tank from the engine. At the engine end a rubber hose is factory crimped onto the tube. The hose is known to split, and it is conveniently located above the headers. This is a somewhat high pressure app, 40 PSI or so, and fed by an electric pump at the rear of the car. Hence my desire to replace it with Aeroquip (cutting the tube back to inside the wheelwell so that the obvious failure point is not RIGHT above the headers...) before it becomes a carbecue. If I can make it work not only will it look sexy but it will be a hell of a lot cheaper than dropping the rear suspension to replace the stupid steel tube, which is in fine shape, just the hose is gone (actually replaced at the moment with some high pressure hose simply clamped on with t-bolt clamps)

thanks!

nate

Reply to
Nate Nagel
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Have you tried Summit? I see they have various AN-Metric adapters.

Reply to
Pete C.

I see that, but where do I get the metric tube nuts? I have been unable to find a source. I *do* have a bubble flare tool although I lent it to a friend to replumb his Corrado's brake system.

nate

Reply to
Nate Nagel

BTW at least as of six months ago a lot of that stuff wasn't in the Aeroquip catalog. I will have to check back with my local supplier (up the street) they were helpful but no help when I first started looking back around February. I had a little issue with the DME so the car sat for a while.

nate

Reply to
Nate Nagel

You might give them a call or email and ask. It would seen there are a few ways to assemble things so they might have a combo that would work if they know the from and to.

Reply to
Pete C.

I did drop Aeroquip a line to see what they had to say.

I found this kit online:

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seems to be the nicest of the three available, but my mechanic is having some heartburn about the use of compression fittings on the hard lines. I think I may end up just buying it and using it as is anyway unless I can find some flare fittings, because a) the connections are relocated to the outside of the inner fender, b) the compression fittings are theoretically rated for the pressures experienced and c) I can't seem to find an easy way to improve on the kit.

I could also simply replace the one line that's failed with the factory replacement parts - the new line now comes in two pieces, joined with a union under the car. However, that brings me right back to the inability to find the tube nuts and unions to make this work.

Either my google-fu is weak, or else there's not a whole lot of aftermarket support for metric flare fittings...

nate

Reply to
Nate Nagel

If the fuel pressure is really 40 PSI, the potential separating force on your 10mm connections (about 1/8 sq. in. area) is about 5# so damn near any type of connection should hold just fine.

Reply to
Pete C.

I agree, this exercise is as much an exercise in keeping the "massive overkill" desires of the race-centric shop that I take my car to satisfied as it is making the car safe. Truth be told I think the car is probably safe as is so long as I keep an eye on the new hose (that's been on there for at least three years or so) but this is the only shop that I've found that I have a good feeling about, and I'll make some concessions to keep them happy. Apparently it is not entirely uncommon to see a flaming 944 at the track due to the age of the cars and the less than intelligent routing of the rubber fuel hoses. Thus proving that Porsche apparently learned nothing at all from the 914, but I digress. I just refuse to pay the shop $1K plus to drop the rear suspension to replace the whole hard line back to the tank - that in their opinion is "the right way" to do it, but I would much rather invest in the AN stuff, then if the hose ever goes bad again I can just go to my local speed shop and get another couple feet of -6AN hose and be done with it.

However, I *would* like to find a source for metric flare nuts and fittings anyway, just so that I can do stuff in the future. I do have access to some metric brake line fittings but haven't been able to find anything larger.

nate

Reply to
N8N

Try checking your local Parker store / dealer. Parker has all things fluid, particularly hydraulic and there is a lot of metric hardline hydraulic stuff around.

Reply to
Pete C.

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