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JohnMc

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Discussion starter · #1 ·

I have been fighting fuel leaks all day. I have tried several combinations of lines and fittings. They all leak. I have a electric fuel pump in my 57.
Note the pictures.
If Houston had any hills I might go jump off one.
Suggestions? Does anyone make a pre-made hard line setup that replaces the whole thing?
JohnMc
 

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I had fuel leaks in the same sort of places, nothing a little teflon tape and an extra turn on the fittings didn't fix. Any way to eliminate that compression fitting at your filter? Like flare the end of that tube and hose clamp it right to the filter? That'll eliminate one spot.
 
"If Houston had any hills I might go jump off one.
Suggestions?"

An overpass. Or the ship channel bridge. :sign0020:

I would get rid of the compression fittings. Use steel line, double flare it, and use inverted flare fittings/tube nuts. Eliminate the extra fittings like the coupler. You can buy varying lengths of pre-flared line at the auto supply. That's the closest to "pre-made".

Teflon tape and an extra turn is for pipe threads/fittings only.
 
Discussion starter · #4 ·
Fuel Line

Thanks Guys
I took the whole thing back out (pic)
Rick- Inverted fittings? I think I need a better auto parts place. The one near me is an Autozone and those guys are no help. Maybe if I take the line over NAPA or somebody can lay out what I need.
John
 

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IMO compression fittings shouldn't even be allowed on a car!!! Rick has a good plan with the inverted flare fittings, might want to invest in a tube flaring kit for double flared fittings and a tubing bender. These tools will pay for themselves quickly just in the amount of trips it saves to the store to try to find something that may or may not work!!!!!

Another choice would be to use a pipe to AN fitting at the fuel pump, a 37 degree flaring tool, some aluminum fuel line tubing (cheap) and the appropriate sized tube nuts ad sleeves. Can even step up the appearance level a notch with this method and use stainless braided hose or stainless tubing. More expensive, sure! But when done properly it will work fine and last a long time!
 
your picture shows tube nuts with presumably flared ends on your metal lines. these will leak robustly if the ends are not flared properly, evenly, and at the same angle as the brass connectors. same thing with brake lines. If you have metal lines with flared ends, you can take regular fuel rubber hose and just put it over the ends of the metal lines with hose clamps. It is not the right way to do it, but if the system is a low pressure system with a carburetor, it will work fine (and has worked fine for 20 years on one of my cars).

the question is what is the end flare on your metal lines, and who flared it? if you did it yourself with one of those cheap flaring tools after you cut the lines yourself with a tubing cutter, odds are the flared ends are not symmetric -- when using a tubing cutter (one of those metal wheels you twist around the tube while you tighten it), you harden the end of the metal line, so that when you flare it, it flares unevenly. I made up all my own brake lines and it took me two or three tries on each fitting before i figured it out. Using a small cutoff wheel on a dremel tool does not harden the ends, and gives you good flares. maybe I am off topic here.
 
Discussion starter · #7 ·
JKG
No you are not off at all.
I, in fact did my own flares and they could very well have been slanted a bit.
I like this- Advice that can be used quickly and easily. I have a double flare tool but I go the "easy" route and make a single flare. Just another example of laziness or trying to do things on the cheap that bite you later.
John
 
carl, one more time, you don't use teflon tape on anything other than a pipe fitting.

JohnMc, you need to double flare steel lines when inverted flare fittings are used. If nothing else, the tube nut may bottom out before the flare seals if you have a singe flare. Double flares are thicker, and the other problem with single flares is that they may crack, and with the thinning of the material in the flare, an offset or misalignment can occur more easily.

Glad to hear you didn't jump off the ship channel bridge - yet. Hang in there.
 
Having shopped for a flaring tool to do some brake lines, I got the impression that there are a lot of low/ mid priced tools that only make leaky flares, and you need to buy an expensive one if you want it to actually work. The quality of tubing varies a lot too, there may be a connection to American manufacturing having moved to China.
 
i Have had a ton of experience making double flares in tubing for brake lines. i have so much experience because i had to do each two or three times before I figured out the tricks. here are my suggestions:

1. get good quality tubing - i prefer NOT stainless steel, just regular steel. the stuff from classic tube or stainless tube seems a lot nicer than the garbage from the local parts store

2. cut it with a small cut off wheel on a dremel, not a tubing cutter. As mentioned above, it seems the tubing cutter hardens the metal and that makes poor flares.

3. I got one of the very expensive hydraulic flaring tools. it seems the kit is sold by a lot of people - it really is 100 times better then the usual made in china flaring tool.

4. look at the flares when they are done - if they are not perfectly round and symmetric, they will leak.

for tubing like this, the seal does not come in the threads of the nut. teflon tape will not do anything. The seal comes from the tubing mating with the inverted flare of the fitting. double flares for steel tube. single flares for stainless steel, but more concerns for leaks and cracks with single flares.

when you buy bulk tubing if you do an entire car yourself, but at least 50% more than you need, for when you mess up the final flare, or when you kink the tubing trying to bend it.
 
"Having shopped for a flaring tool to do some brake lines, I got the impression that there are a lot of low/ mid priced tools that only make leaky flares, and you need to buy an expensive one if you want it to actually work. The quality of tubing varies a lot too, there may be a connection to American manufacturing having moved to China."

All good observations.

Although someone recently posted a problem with one, I have and recommend a Ridgid 345DL flaring tool. Paid about $70 for it. Not that much more than one that doesn't work.

The steel tubing that I can get at the local auto supplies (pre-flared in various lengths) has a green coating and seems quite hard. It doesn't re-flare or bend well.

Summit has bulk tube in 25' lengths and that stuff seems to work ok.

I have purchased SS tube from Inline Tube and it bends and flares quite well. I'm sure their plain steel tube is equally suitable for bending and flaring.
 
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