Fuel line help needed

[JRouche]

Ok, super simple question. How the heck do I plumb hard lines?? Hahaha. Yeah really. I see all types of info on plumbing soft lines. AN fittings and all.

And thats what I have already, soft lines. I have a 62 nova with EFI and a fuel cell. Years ago I bought some pretty expensive fuel line designed for EFI. And its not failing, but I dont want it to get to that point. So I have the rubber line all the way from the cell to the engine.

Well I want some piece of mind and hard lines.

So... The fittings? Are they just a compression flare? For the life of me I cant find a simple article anywhere talking about the line ends. I need to go from a NPT on the cell to a NPT on the pre-filter to the pump. The pump is also NPT. Then to another filter, also NPT.

Any help on what fittings and what flare I use with the hard line?? Thanks ahead of time for any help.. JR

So.. Im gonna get some 3/8" hard line, aluminum or stainless. But what I need to know is where do I get the fittings. Maybe not so much where, but what is the flare for hard fuel line. What type of fitting is used?????



And help guys? Thanks abunch... JR

[Yelcamino]

Ok, super simple question. How the heck do I plumb hard lines?? Hahaha. Yeah really. I see all types of info on plumbing soft lines. AN fittings and all.

And thats what I have already, soft lines. I have a 62 nova with EFI and a fuel cell. Years ago I bought some pretty expensive fuel line designed for EFI. And its not failing, but I dont want it to get to that point. So I have the rubber line all the way from the cell to the engine.

Well I want some piece of mind and hard lines.

So... The fittings? Are they just a compression flare? For the life of me I cant find a simple article anywhere talking about the line ends. I need to go from a NPT on the cell to a NPT on the pre-filter to the pump. The pump is also NPT. Then to another filter, also NPT.

Any help on what fittings and what flare I use with the hard line?? Thanks ahead of time for any help.. JR

So.. Im gonna get some 3/8" hard line, aluminum or stainless. But what I need to know is where do I get the fittings. Maybe not so much where, but what is the flare for hard fuel line. What type of fitting is used?????

And help guys? Thanks abunch... JR

If you've never done this before then I'm probably oversimplifing it... If you have a 37* flaring tool you can use tube nuts and sleeves to adapt your hard line to the AN male ends. You get NPT-AN male fittings for your components, then slide the tube nuts/sleeves on your hard line, flare the ends to 37* and then you can attach the hard lines to the AN fittings.

[CarlC]

Carroll Smith's "Nuts, Bolts, Fasteners, and Plumbing" is a great guide and well worth the purchase cost.

[JRouche]

Ok, thats what I was kinda thinking, I just needed some back up on my thoughts. I have a mastercool hydraulic flaring kit. Of course it doesnt come with the 37* dies. Sup with that Ok, pretty simple. Now I just need to get the dies I need. Thanks for the help. JR

If you've never done this before then I'm probably oversimplifing it... If you have a 37* flaring tool you can use tube nuts and sleeves to adapt your hard line to the AN male ends. You get NPT-AN male fittings for your components, then slide the tube nuts/sleeves on your hard line, flare the ends to 37* and then you can attach the hard lines to the AN fittings.

[JRouche]

Carroll Smith's "Nuts, Bolts, Fasteners, and Plumbing" is a great guide and well worth the purchase cost.

Yer soooo right. I actually have three of his books. The two suspension books are all tattered and dog eared. The NBFP book still looks new. Guess I should read that one huh Thanks, Ill be reading through that one tomorrow morning with my jug of coffee. JR

[parsonsj]

I have a 37* flare tool (3/16 to 5/8), and Ridgid benders for all the sizes. Total investment of of at least $500.

I would recommend you use aluminum .035 wall straight tube. Avoid the coils of 25 feet of aluminum tube... it's too hard to straighten, and too soft for good flares. Figuring out the routing of the lines, and measuring the bends is tricky, but the bending tools help a lot by providing good indicators of where the center line of the tube will end up after the bend.

Oh: the 25' coils are good for one thing: prototyping and practice. It's cheap, you can learn what you are doing, and then you throw it away and get straight tube and go from there. I can't recommend stainless tube, especially for fuel lines. It's too hard to work, too expensive to buy, and too prone to flare leaks. If you do go with ss lines, here are my best tricks for getting them to seal properly:

1. Make sure the SS is annealed tube.
2. Use aluminum adapters and unions. The softer aluminum will conform better to stainless flares.
3. Get some valve lapping compound, and some steel fittings. Put the compound on the ss flare area, and finger tighten the line to a corresponding steel fitting. Do the "fitting lapping" thing for several minutes. It will give you perfect flares that don't leak. This is unnecessary on aluminum tube...
Bonus tip: Keep some "flare savers" or "conical seals" for the one flare that does leak. I've not used them, but others report success in saving a leaking flare joint.

Have fun!

jp

[parsonsj]

Here's a great place for flare tools:

http://www.purechoicemotorsports.com/

This tool will work great for aluminum and mild steel. It is marginal for stainless (see my 3 tips above):

http://www.purechoicemotorsports.com...prod/prd46.htm

jp

[b-man]

My fuel system install on my GTO, 1/2" and 3/8" aluminum line (from 25' rolls) and steel hard lines, with a few inches of rubber fuel hose for the fleaxible connections. All of the tube fitings are brass inverted flare (45 degree) just like the OEMs used on fuel systems 'back in the day':

http://forums.performanceyears.com/f...5&postcount=60

Trans cooler install on the GTO using 3/8" steel hard line with brass inverted flare fittings:

http://forums.performanceyears.com/f...6&postcount=27

Twin-trans coolers plumbed with, you guessed it, 3/8" steel line and brass inverted flare fittings:

https://www.pro-touring.com/forum/sh...=48361&page=14

Hope this gives you some ideas.

[CarlC]

The conical seals work very well. Aircraft Spruce is the least expensive source I've found.

[JRouche]

Thanks John.. I have the MC 71475 kit. Dunno why they didnt supply the 37* dies. I found them for about 77 bucks. On order now. I used the flaring tool to plumb the entire brake system. All straight line and fittings. Coils are a bear to get straight again for the long runs on a car. Ummmm, I HATE routing tubing. Hate it. I just dont have the vision to get the bends in the perfect spots. Too short, too long, too short and long. What I end up with is usable, just not great looking like so many plumbing jobs Ive seen. Thanks for the tips. JR

I have a 37* flare tool (3/16 to 5/8), and Ridgid benders for all the sizes. Total investment of of at least $500.

I would recommend you use aluminum .035 wall straight tube. Avoid the coils of 25 feet of aluminum tube... it's too hard to straighten, and too soft for good flares. Figuring out the routing of the lines, and measuring the bends is tricky, but the bending tools help a lot by providing good indicators of where the center line of the tube will end up after the bend.

Oh: the 25' coils are good for one thing: prototyping and practice. It's cheap, you can learn what you are doing, and then you throw it away and get straight tube and go from there. I can't recommend stainless tube, especially for fuel lines. It's too hard to work, too expensive to buy, and too prone to flare leaks. If you do go with ss lines, here are my best tricks for getting them to seal properly:

1. Make sure the SS is annealed tube.
2. Use aluminum adapters and unions. The softer aluminum will conform better to stainless flares.
3. Get some valve lapping compound, and some steel fittings. Put the compound on the ss flare area, and finger tighten the line to a corresponding steel fitting. Do the "fitting lapping" thing for several minutes. It will give you perfect flares that don't leak. This is unnecessary on aluminum tube...
Bonus tip: Keep some "flare savers" or "conical seals" for the one flare that does leak. I've not used them, but others report success in saving a leaking flare joint.

Have fun!

jp

[JRouche]

Hey Bart. Thanks for the links to your car. Some good looking bends. Im sure Ill get some ideas. I am gonna go with the 37* flare because I will be using stainless steel braided hose (teflon lined) for the flex areas. With that hose the AN style fittings are really all you can use, no hose clamps are going in. Thanks, JR

My fuel system install on my GTO, 1/2" and 3/8" aluminum line (from 25' rolls) and steel hard lines, with a few inches of rubber fuel hose for the fleaxible connections. All of the tube fitings are brass inverted flare (45 degree) just like the OEMs used on fuel systems 'back in the day':

http://forums.performanceyears.com/f...5&postcount=60

Trans cooler install on the GTO using 3/8" steel hard line with brass inverted flare fittings:

http://forums.performanceyears.com/f...6&postcount=27

Twin-trans coolers plumbed with, you guessed it, 3/8" steel line and brass inverted flare fittings:

https://www.pro-touring.com/forum/sh...=48361&page=14

Hope this gives you some ideas.

[The WidowMaker]

jp - any reason you didnt use a conical seal at every fitting? thats my plan and i want to make sure there are not negatives.

Tim

[parsonsj]

Tim,

No real reason... mostly I didn't know they existed. I had one fuel flare fitting (ss) that had an annoying weep, but tightening the nut seems to have cured it. I had another power steering line (also ss... see the pattern?) with some weeping, but I fixed that with the lapping method. If I had had a conical seal I would have used it, but I didn't want to have my car down for a week while I got the seals in.

Other than that.. no problems. I must have 50 hardline flares on my car. Those are the only two I've had any problem with.

jp