copper fuel lines GOOD or BAD

Well ! I have used copper in one car from the tank to the pump that's driven weekly .It was put on in 1985 so that's 28 years,I have no desire for the rust build up in in a steel line from a car that can sit around .The steel has a coating and its unlikely to be coated on the inside .this is the in ward side so no presser is involved ,I expect it will do another 18 . I worked on a 34 that had a complete hydraulic conversion that had copper pipes on it (put on in the States not legal here ) my best option was to replace a section with Bundy tubing .during the discussion with the suppler I commented that it may be surprising how much pressure it would take to burst a copper pipe ,he decided to check it in his book and it listed as 500 PSI, Its unlikely you could do that with your foot ,,
 
FlatheadTed said:
.during the discussion with the suppler I commented that it may be surprising how much pressure it would take to burst a copper pipe ,he decided to check it in his book and it listed as 500 PSI, Its unlikely you could do that with your foot ,,
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I've heard brakeline pressures can be upwards of 2000psi...I'll see what mr Google says...

Googling shows 800-2000psi (max effort) on various sites.
 
i cannot win. Put a copper plated steel fuel line in a car, 3 months later it is a rust plated steel fuel line. i bought a car with hydraulic brakes, drove 200 meters down the road & a rusted hose burst so i twisted it closed with pliers. Twisted hoses shut about 20 times on the way home & only had 1 wheel brake left when i got home. Some old man said we should replace the brake lines with heavy copper tubing that will not rust so we did. Now you think that makes me cheap & that is wrong? i cannot win. Either rust out or get a leak through fatigue, eventually. i have no test for the copper without moving it to see how hardened it has become without moving it which will harden it, essentially a destructive test.
i would take up replacing the copper tubing as routine maintenance but the whitworth thread fittings are unobtainium.
 
Corrosive environments do require special materials. Even stainless can corrode in salt water bath over time. Marine and aviation equipment use a lot of epoxy chromate primers now days to ward off the cancer. Red lead was better but is near extict due to environmental limitations. Bronze works OK as a propeller or propeller shaft but doesn't make good tubing. I've known a few helicopter mechanics that worked on tuna boats for the high pay they could earn but they were constantly washing there equipment with fresh water and 55 gallon drums of WD-40. One guy must have had 20 coats of zinc chromate primer on his tool box to keep it from falling appart. I always figured they earned every penny they made.
 
I would not use copper on the pipe from the pump to carburettor because of the possible frequent removal the copper can compress at the olive to ferral compression fitting and leak .
 
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I will never understand why this is even questioned. Ford and others used copper coated steel fuel line tubing for a reason and it was not economics,copper back then was probably cheaper to make than processing copper coated steel. Copper coated steel is available but not at Lowe's or Menards or Home Depot so most people take the quick lazy way out and buy the copper. Those same lazy people that bought copper refrigeration or plumbing copper tubing get on Fordbarn and say it is okay to use and may even be better. At least one of those same lazy people who bought their fuel line at Home Depot and say its okay and want you to use it also never drive their 36 Ford anymore. Don't be one of those same lazy people who never drive their old Ford anymore.:(
 
I am working on a 1930 Aurburn that has copper on the brake lines from the factory I wouldn't use it on brake line though ,I think most of the paranoia surrounding copper comes from here say .were are the real tests ,28 years and counting , I used it at the time because I wasn't aware of the availability of copper coated tube . You may get some fatigue as on a high frequency application such as a chain saw ,but that would apply to steel as well .What fuel line would you put in the bilge of a boat ?.The difference between steel and copper for fuel lines in my book is minor ,so do what ever presses your buttons.
 
I use copper fuel line on my 30 coupe which I have a model B carb, I use copper on each end with rubber in between.
 
When i was a young man and knew everything, i had a 34 Plymouth coupe with a 58 Cadillac drive train. A brake line rusted off and i decided that using steel was stupid because it would rust so i replaced it with a copper line at work. I drove home and before i got to work the next morning i went to stop going a little fast and the brake line split open. I did not wreck and got it to work and installed a steel line before i left work. I never ever used copper line again.
 
If this thread was long and contested, lets discuss the merits of DOT 3 versus DOT 5 and see if a conclusion can be reached.
 
Perhaps those who have used copper tube could tell us the wall thickness they chose and the Grade. Like many other things copper tube comes in a variety of W.T and qualities. Also the hardness would be a major factor; from fully annealed to half-hard to hard.
 
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Fe26 said:
Perhaps those who have used copper tube could tell us the wall thickness they chose and the Grade. Like many other things copper tube comes in a variety of W.T and qualities. Also the hardness would be a major factor; from fully annealed to half-hard to hard.
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Here is a typical roll available over the counter from any motor factors.

It says 8000 psi test pressure rated, 22 guage wall thickness,

For the difference in price though, I would / do use, Cunifer.....a lot of manufacturers use it now, including Aston Martin among others.

I guess steel pipe is fine in dry warm places but if your roads see salt during the Winter months, Id use the copper/ nickel.

One of the main M.O.T. Test failures are corroded brake lines over here.
 
Copper brake pipe has generally superseded steel. Due mainly to the problem of corrosion. My 3 year old Peugeot failed its first MOT due to corroded steel brake pipes. I made my own up out of Cunifer (Cu-copper, Ni-nickel, Fer-iron). 88.6% copper, 9.2% nickel, 1.4% iron, 0.8% manganese.

Many car manufacturers have gone to copper alloy (ie C70600) for brake pipe including Volvo, Rolls Royce, Lotus, Aston Martin, Porsche and Audi.

When properly installed, copper alloy would also make excellent fuel pipe.
 
It must be stated that there is a world of difference between the copper/copper alloy pipes that are specifically designed for brake pipe usage and the copper pipe typically found in your typical US hardware store.

I bought some fuel pipes in the USA from an early ford supplier and the pipe was copper. Really soft thin wall rubbish. I only bought them to get the fittings.

I have used pipe similar to that posted above but get the Kunifer type if I can.

So copper pipes for fuel pipes - good or bad?

I'd have to say BAD. Unless you can get the good stuff designed for the brakes. Then it's GOOD.

Mart.
 
Fe26 said:
Perhaps those who have used copper tube could tell us the wall thickness they chose and the Grade. Like many other things copper tube comes in a variety of W.T and qualities. Also the hardness would be a major factor; from fully annealed to half-hard to hard.
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I purchased a roll of brand new 1/4" OD copper tube at a large industrial salvage yard. Some time later I needed a new pump to carb line and cut a piece of it. It turned out to have a 1/8"-.125 ID. I decided to use it and see how it would work knowing the inlet hole in the needle valve has a .098
hole. It worked fine with no flow restrictions at 75MPH and has been on the car for a number of years. I have use annealed standard 1/4" OD copper on 5 or 6 old Fords for fuel lines. Clamped at the rear cross member, along the frame and a flex hose at the fuel pump it presents no problem. The only place there can be flexing of the fuel line is at the firewall. Going down the road is not where the problem it is between the firewall and pump where flex hose does it's job from the movement of the engine when it rocks as the RPM's increase. G.M.
 
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Mart said:
It must be stated that there is a world of difference between the copper/copper alloy pipes that are specifically designed for brake pipe usage and the copper pipe typically found in your typical US hardware store.

I bought some fuel pipes in the USA from an early ford supplier and the pipe was copper. Really soft thin wall rubbish. I only bought them to get the fittings.

I have used pipe similar to that posted above but get the Kunifer type if I can.

So copper pipes for fuel pipes - good or bad?

I'd have to say BAD. Unless you can get the good stuff designed for the brakes. Then it's GOOD.

Mart.
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hello mart ,I,m a bit confused , a few weeks ago I renewed all the braking system on my recently imported 51 f1 truck (the brakes were totally shot and the steel brake lines cracked with interior rust as soon as I started to remove them),I have replaced the lines with copper brake pipe bought from my trusted local motor factor ,I mentioned this subject to him and his reply was that they have been sold for years with no problems ,I havnt used the truck as its pretty much apart but now this has put a giant question mark in my head,
your last paragraph mentioned copper pipe "unless you can get the good stuff for designed for the brakes" does this mean all copper pipe that's designed for brakes would be good in your opinion? I,v got this nagging feeling I should do the brakes again using something else but I don't know what ,have you or would you use copper brake pipes ? thanks jim.
 
37coop said:
your last paragraph mentioned copper pipe "unless you can get the good stuff for designed for the brakes" does this mean all copper pipe that's designed for brakes would be good in your opinion?

jim.
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Yes, Jim, it should be fine.

The point I was trying to make was that that stuff is easily available over here, but I suspect it is hard to find in the USA and people will probably get some inferior stuff if they do try and buy copper pipe over there.

Mart.
 
Mac's along with some other vendors sell tank to engine copper fuel lines. The fact that nobody here has slamed Mac's tell's me a lot of you are fine with properly installed copper.
 
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