Can copper be used for fuel line?

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Longgone

John/68 Barracuda & Dart
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Can copper be used for fuel line from the fuel pump to the carburetor? Is it not used just because it`s soft or what? I would love to custom flare and bend a nice tight fuel line for the beast but my flaring tools won`t do the harder metals. Any help?
 
I've been told by a mech & plummer it's not a problem as the fuel lines psi is not that high....as for brakes, trans...a no-no. It's obvious steel is much stronger, so that's why it's used. However, there could be "laws" written somewhere that would say no way as the copper would brake EZer.
 
I've seen copper used numerous times for fuel lines. The one problem copper has in an installation such as this is that it "work hardens" and becomes brittle over time due to vibration, at which time it can crack. Aluminum tubing would be a better choice and is just as easy to bend. If you need sources PM me and I'll link you to some. Aluminum is used exclusively in aircraft with excellent results.
 
I'll second the 'heard it will deteriorate due to vibration and eventually fail faster than much faster than steel or aluminum' as well
 
I have copper fuel line on my Duster...no problems...not to say failure is not possible, but i have worked as a mechanic for 10+ years and used alot of copper and ive never seen it break due to vibration or age...I have seen it chaffed through, but ive seen steel chaffed thorugh too...my buddy even used it for brake lines for years (yes, its a no-no according to the law) and he says hes never seen one blow
 
Longgone said:
Can copper be used for fuel line from the fuel pump to the carburetor? Is it not used just because it`s soft or what? I would love to custom flare and bend a nice tight fuel line for the beast but my flaring tools won`t do the harder metals. Any help?
check with the department of transportation safety laws before using any copper on any lines. Here it is 100% against road safety laws to use copper gas lines. ask yourself," why did the car not come from the factory with any copper lines anywhere"? If spotted on a car during a safety inspectgion the car will not pass and the lines must be changed to steel ones.

kenny b
 
kenny b said:
check with the department of transportation safety laws before using any copper on any lines. Here it is 100% against road safety laws to use copper gas lines. ask yourself," why did the car not come from the factory with any copper lines anywhere"? If spotted on a car during a safety inspectgion the car will not pass and the lines must be changed to steel ones.

kenny b
Don't disagree - but its kind of interesting to note in many of the fuel pressure guage kits you can buy copper tubing is supplied with the installation. too each his own.

"Brakes lines" :butthead: - God must really be watching over him
 
kenny b said:
check with the department of transportation safety laws before using any copper on any lines. Here it is 100% against road safety laws to use copper gas lines. ask yourself," why did the car not come from the factory with any copper lines anywhere"? If spotted on a car during a safety inspectgion the car will not pass and the lines must be changed to steel ones.

kenny b

Just a point...
I would have to agree and not arguing with you about the laws or inspection stations. However many things are only a "standard" and don't even really fit into safety. I don't think having copper tubing means your car will blow up or kill you if the tubings rating is above the pumps PSI. We know some Honda guys would try and use coloured "plastic" hose if they could, and that's why there's standards. This is the same as the law states you can "only" have amber or white turn lights up front (does having blue mean you'll be in an accident).....No, there just standards that must be met. Same as tinting windows in (BC)....Driver & Passenger can't have it unless came DOT approved...What's up with that?? So again, if safety's not an issue in what you modify, but just a standard...it's just taking a chance not to get caught.
 
You can do what ever you want on your car, hell, I've seen some pretty odd things. I myself only use steel line if it is to be a hard line. Copper for the most part is not supposed to be used, I don't know why or care why, it just isn't. I not one of those guys that have to question everything in life and I am not going to be a test dummy because I think something will work just fine. I have seen plastic line run to a fuel pressure gauge inside the car once and that same guy argued that he has been running it like that for years and I was the *** for not passing his car in tech. So you guys that want to be self engineers, go right ahead, but don't sell it to other people when it's not the correct way just because it worked for you. Someday someone else may own one of these self engineered cars and may cause an injury or death. I will tell you if I purchase one of these self engineered cars and don't catch the problem until it harms me are my family there will be a death involved, it will be the guy that did it.

Why would you not use a steel line? to lazy or cheap to buy a bender or you can bend the copper by hand? M.I.C.K.E.Y M.O.U.S.E


Chuck
 
340mopar said:
You can do what ever you want on your car, hell, I've seen some pretty odd things. I myself only use steel line if it is to be a hard line. Copper for the most part is not supposed to be used, I don't know why or care why, it just isn't. I not one of those guys that have to question everything in life and I am not going to be a test dummy because I think something will work just fine. I have seen plastic line run to a fuel pressure gauge inside the car once and that same guy argued that he has been running it like that for years and I was the *** for not passing his car in tech. So you guys that want to be self engineers, go right ahead, but don't sell it to other people when it's not the correct way just because it worked for you. Someday someone else may own one of these self engineered cars and may cause an injury or death. I will tell you if I purchase one of these self engineered cars and don't catch the problem until it harms me are my family there will be a death involved, it will be the guy that did it.

Why would you not use a steel line? to lazy or cheap to buy a bender or you can bend the copper by hand? M.I.C.K.E.Y M.O.U.S.E


Chuck

Holly freak Chuck....down boy. LOL I was only talking "safety" vice "standards" You kinda have to read between the lines what my point was. I agree, giving out bad information or direction is NOT a good thing and what we don't want to see. (common sence)!! However, just about everything we do with our classic's are mostly "not" done by licenced mech....To tell ya the truth...I think there's quite a few self engineered cars here. From welding to electrical to brakes. I don't think his idea of copper tubing had anything to do with being lasy or cheap. He was just asking a question. Chuck...did you have your coffee today? Here's one on me :coffee2: LOL :thumbup:
 
Back to the original question.......
"Can copper be used....."
Answer; Yes. Is it adviseable? No. Reason being, copper gets brittle and work hardens, and you can't tell until it cracks.
 
okay, im throwing in my 2cents worth. i install heating and a/c systems for a living. the newer systems use 410a freon which runds about 300-400psi when the system is running. the refer lines are soft copper. the equipment also shakes-vibrates a bit while running. ive seen very few that leak when installed properly. that being said, i am using 3/8 copper for my fuel lines on my car, but also putting 3/8 rubber fuel line over it anywhere it may rub against metal. i say go for it.
 
it costs 30 bucks for 20-25 ft. of steel line, including stainless and 20 bucks for aluminum. why go to copper? once again, its your car do what you want. in my shop, STEEL ONLY. end of discussion. aluminum is for race cars and planes where weight is an issue. if you cant' flare, use the tubing adaptors from earls to go to steel braided hose. scimp on valve covers or an air cleaner, something that does not affect your safety, but not fuel system components.
 
sweatybetty said:
okay, im throwing in my 2cents worth. i install heating and a/c systems for a living. the newer systems use 410a freon which runds about 300-400psi when the system is running. the refer lines are soft copper. the equipment also shakes-vibrates a bit while running. ive seen very few that leak when installed properly. that being said, i am using 3/8 copper for my fuel lines on my car, but also putting 3/8 rubber fuel line over it anywhere it may rub against metal. i say go for it.

You have to ask yourself....What is the biggest benefit vs. risk ratio to having Copper Lines? Benefit of cooling/heatsink effect? If so, I imagine it would be theoretically minimal compared to the properties of aluminum. Just like the arguement for aluminum vs copper radiators. It's all in the design/setup.

I'm not a metallurgist but if it was insulated somehow that might be another story. An effective ceramic coating (great heat sinks) on the outside walls of the fuel lines could dissipate heat as well, especially if it was coated near the headers/exhaust. Same goes for brake lines that run near hearders. With all these special coatings engine builders are using these days I bet there would be a market for this kind of thing if it could be proven to be effective. That's with scientific testing and not "mickey mouse" engineering :-k
 
The rubber lines in your fuel system are more likely to fail than copper line, ever hear of dry rot? How many have changed out all of the little sections of rubber line in their fuel system, or do you just wait until you spring a leak to realize you should replace that 4 inch piece that attachs the pick up tube in the tank to the line that runs to the engine (there are other short pieces on the vent and carbon canister lines also in few places). How many of you use plastic or those glass see thru fuel filters (hmmm, wonder how they can be considered safer and yes I am well aware that most race sanctioning bodies limit rubber line overall length in the fuel supply system and that they do not allow glass or plastic fuel filters. I am refering to street vehicles in this respect).

Aluminum and steel can work harden and fail just like copper (ever bend a piece of coat hanger back and forth until it breaks or how about picking up some aluminum filler rod and trying the same thing?). Make sure lines are secured properly, to avoid vibration fatigue.

All will corrode due to exposure to elements. If you use either consider painting the lines to help protect them from the elements if it will be street driven.

Soft copper line is more expensive than aluminum line. Would be the main reason I would avoid it, but if I had a roll of soft copper line the correct size anyway and didn't have to spend money to buy aluminum, I certainly wouldn't be afraid of using it as a fuel line.

JMO
 
Copper will work harden, not just with vibration but with heat cycles as well. That is why we replace the pure copper spark plug washers on aircraft engines (or anneal them) each 100 hours.
Copper fuel line is more expensive, because.....copper is more expensive.
Ever see a car on fire in the middle of the road? Use whatever you want, it's your car. I myself have plenty of copper tubing available, but won't use it. Aircraft fuel lines are either stainless steel, aluminum, or braided steel teflon. Copper is only allowed on primer lines.....which frequently break! I've never seen a steel or aluminum line break except in an accident. I rest my case.
 
My flaring tool will only do soft metal (like copper) and I have a ton of it laying around the garage. I have the tools and the material and that`s why I was asking if it was used. I tried using steel and I can`t flare it without the edges cracking and I`ve also had a hard time making the sharp bends I need to get around the distributor and down to the pump. I guess I`ll just have to buy a steel flaring tool and some line to bend the piece I need. Boy, there`s just NO saving money at this hobby ,huh!
 
Captainkirk said:
Copper will work harden, not just with vibration but with heat cycles as well. That is why we replace the pure copper spark plug washers on aircraft engines (or anneal them) each 100 hours.

So does aluminum, if you had any metulurgy background you would know that. Also, compare apples to apples, not apples to cow dung. We are talking fuel line, not engine components in direct contact with the combustion chamber, if your fuel line is exposed to over 200 degrees along the underside of the vehicle, I have a feeling you have much bigger problems to contend with, and aluminum line is not going to solve it or save you. Also, the purpose of annealing or replacing the copper spark plug washers, in aircraft, is because you have removed it for service. The washers are/will be sufficiently hardened and will not compress properly upon reinstallation if you do not address the issue and you will not get a good combustion seal which is CRITICAL to an aircraft engine. Hmmmm, your very statement brings up a point, if the hardening of the copper was so dangerous (ie, causes cracking and failure of said copper, cumbustion chamber pressures FAR exceed fuel system pressures) why would the FFA even allow copper to be used, why not the all mighty steel or aluminum your touting? I will answer for you, because it isn't the death and destruction causing failing material your trying to make it out to be.

Captainkirk said:
Copper fuel line is more expensive, because.....copper is more expensive.

Noooooooooo, really, I think I said that :)

Captainkirk said:
Ever see a car on fire in the middle of the road? Use whatever you want, it's your car.

As a matter of fact, yes, many many times. Guess what, most I have seen were caused by one of a very few things
1. Injector O-ring or fuel line o-ring failure.
2. Electrical short somewhere in the dash (how many of my fellow mopar fanatics have run into this one, can we all say AMP meter!)
3. Vehicle parked over combustibles (dried grass, leaves) and fire started by catylitic converter heat.
4. Vehicle owner/operator ignorance, I have seen cars burned to the ground because of cigerettes dropped into the seat, under the seat, or just left in the ash tray (also know one very young fool who left an incense burning in his ashtray because he was trying to cover up a smell in his car from a bad habit of his, the kind that gets u arested if you know what I mean:toothy7: ). NONE I have seen were ever caused by a failed copper fuel line. Not one. (Not to say it is not possible, but it is no more plausible than with any other fuel line.

Captainkirk said:
I myself have plenty of copper tubing available, but won't use it.

Good for you, as you stated, you can use what ever you want, I am not twisting your arm, and I and or everyone else can use what we want. It is America (at least for some of us).

Captainkirk said:
Aircraft fuel lines are either stainless steel, aluminum, or braided steel teflon. Copper is only allowed on primer lines.....which frequently break! I've never seen a steel or aluminum line break except in an accident. I rest my case.

Again here we are comparing cow dung to apples. The discussion is automobiles, not aircraft, there is a huge difference. I have seen steel and aluminum line failed from fatigue, corrosion, and impact damage. Copper and aluminum are more likely to crush or stretch in comparison to steel, rather than rip or fracture.

You are obviously not aware that alot of automobiles had copper fuel lines from the very early days of the model T's on up until not to terribly long ago, and the change to steel lines was made to reduce cost, not because of safety issues.

If you are going to dispute a point and attempt to "rest you case" bring a case first please. :thumbup:

Anyone who can site and show proof of any governing or sanctioning body that SPECIFICLY prohibits copper fuel line, please step forward and do so. I know that the NHRA rules DO NOT (states clearly that {all non-OEM fuel lines must be metalic, steel-braided or NHRA-accepted "woven or woven push-lock.") and none of the local stock car racing orginizations and/or enduro racing sanctioning bodies prohibit it. As for Nastards, good luck, you have to be associated directly with them to get one of thier rule books. :blah5:

Please don't take offense, I am neither slamming you, nor dissing you in any way, I just believe you are uninformed/misguided. You are entitled to your beliefs and statements, respect that I am too. :sunny: BTW, I was an aircraft mechanic in the Navy and my dad was also (he is currently building an experimental high performance aerobatic biplane in his shop)
 
daves66valiant said:
You have to ask yourself....What is the biggest benefit vs. risk ratio to having Copper Lines? Benefit of cooling/heatsink effect? If so, I imagine it would be theoretically minimal compared to the properties of aluminum. Just like the arguement for aluminum vs copper radiators. It's all in the design/setup.

I'm not a metallurgist but if it was insulated somehow that might be another story. An effective ceramic coating (great heat sinks) on the outside walls of the fuel lines could dissipate heat as well, especially if it was coated near the headers/exhaust. Same goes for brake lines that run near hearders. With all these special coatings engine builders are using these days I bet there would be a market for this kind of thing if it could be proven to be effective. That's with scientific testing and not "mickey mouse" engineering :-k

it was FREE. thats the only reason. we throw away partial rolls everyday. it comes in 50' rolls and usually use 25-35' out of that. thet rest gets dumped.
 
You should take all that copper that you're throwing out to the scrapyard and sell it, and then buy some steel. Do it right one time, and then forget about it. JMO, Mike
 
sweatybetty said:
it was FREE. thats the only reason. we throw away partial rolls everyday. it comes in 50' rolls and usually use 25-35' out of that. thet rest gets dumped.
Wow. :tongue9: That could add up to some serious scratch after a year. Scrap prices have gone up too. Free is free, can't get any cheaper than that. I don't see a problem as long as you watch it just like every other vital connections (rubber, fuel filters, etc)
 
I discussed this with my buddy after posting earlier, who is also a mechanic of 30 yrs, and he used alot off copper for fuel lines and says hes never seen one break from vibration,hardening,etc..

of course we use it here for the corrosion resistance more than ease of installation
 
krabysniper said:
So does aluminum, if you had any metulurgy background you would know that. Also, compare apples to apples, not apples to cow dung. We are talking fuel line, not engine components in direct contact with the combustion chamber, if your fuel line is exposed to over 200 degrees along the underside of the vehicle, I have a feeling you have much bigger problems to contend with, and aluminum line is not going to solve it or save you. Also, the purpose of annealing or replacing the copper spark plug washers, in aircraft, is because you have removed it for service. The washers are/will be sufficiently hardened and will not compress properly upon reinstallation if you do not address the issue and you will not get a good combustion seal which is CRITICAL to an aircraft engine. Hmmmm, your very statement brings up a point, if the hardening of the copper was so dangerous (ie, causes cracking and failure of said copper, cumbustion chamber pressures FAR exceed fuel system pressures) why would the FFA even allow copper to be used, why not the all mighty steel or aluminum your touting? I will answer for you, because it isn't the death and destruction causing failing material your trying to make it out to be.



Noooooooooo, really, I think I said that :)



As a matter of fact, yes, many many times. Guess what, most I have seen were caused by one of a very few things
1. Injector O-ring or fuel line o-ring failure.
2. Electrical short somewhere in the dash (how many of my fellow mopar fanatics have run into this one, can we all say AMP meter!)
3. Vehicle parked over combustibles (dried grass, leaves) and fire started by catylitic converter heat.
4. Vehicle owner/operator ignorance, I have seen cars burned to the ground because of cigerettes dropped into the seat, under the seat, or just left in the ash tray (also know one very young fool who left an incense burning in his ashtray because he was trying to cover up a smell in his car from a bad habit of his, the kind that gets u arested if you know what I mean:toothy7: ). NONE I have seen were ever caused by a failed copper fuel line. Not one. (Not to say it is not possible, but it is no more plausible than with any other fuel line.



Good for you, as you stated, you can use what ever you want, I am not twisting your arm, and I and or everyone else can use what we want. It is America (at least for some of us).



Again here we are comparing cow dung to apples. The discussion is automobiles, not aircraft, there is a huge difference. I have seen steel and aluminum line failed from fatigue, corrosion, and impact damage. Copper and aluminum are more likely to crush or stretch in comparison to steel, rather than rip or fracture.

You are obviously not aware that alot of automobiles had copper fuel lines from the very early days of the model T's on up until not to terribly long ago, and the change to steel lines was made to reduce cost, not because of safety issues.

If you are going to dispute a point and attempt to "rest you case" bring a case first please. :thumbup:

Anyone who can site and show proof of any governing or sanctioning body that SPECIFICLY prohibits copper fuel line, please step forward and do so. I know that the NHRA rules DO NOT (states clearly that {all non-OEM fuel lines must be metalic, steel-braided or NHRA-accepted "woven or woven push-lock.") and none of the local stock car racing orginizations and/or enduro racing sanctioning bodies prohibit it. As for Nastards, good luck, you have to be associated directly with them to get one of thier rule books. :blah5:

Please don't take offense, I am neither slamming you, nor dissing you in any way, I just believe you are uninformed/misguided. You are entitled to your beliefs and statements, respect that I am too. :sunny: BTW, I was an aircraft mechanic in the Navy and my dad was also (he is currently building an experimental high performance aerobatic biplane in his shop)

No offense taken, Kraby. Really.
I fully understand that steel fuel line is a ***** to flare (worse yet to double-flare!) And I am well aware that copper line was used for many years on many cars with little or no problems when not subjected to excessive heat or vibration. However, I have no idea if the fuel line he was asking about was in close proximity to heat and/or vibration. I do know something about metallurgy, as a matter of fact. You don't maintain aircraft for thirty years without picking up a thing or two here & there about metallurgy and metal fatigue. My comments were directed at his question "Is it OK to use copper...." assuming he was asking if it was suitable for a project car, not a '67 Nash or a mini van. I realize there is a difference between aircraft and cars. I gave my 2 cents, you gave yours, and let him decide what he wants to do. When I said "I rest my case" I merely meant I'd given my humble opinion on the subject and left it at that.
Copper is NOT the "best choice". Period. (That's strictly my opinion). Will it work? Of course it will. A Holley Dominator will work on a 318, too. :thumbup:
 
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