Is it ok to use copper hard line as fuel line. I have a really nicely done up flathead and don’t really want to use rubber line. My boss was telling me that copper line and fuel don’t mix. The copper does something to the fuel. Is it ok to use copper line as fuel line. Or is my boss correct. Sent from my iPhone using H.A.M.B.
I have used it for over 50 years with never a single problem. Always have a piece of rubber line between the frame and the engine for vibration. But that's just my experience.
There is now a copper nickel fuel break line that's copper color. Copper line itself gets brittle and cracks. https://www.amazon.com/Roll-Copper-Nickel-Fuel-Transmission/dp/B015YGREXU# Jeggs has it also
I used steel brake line for my fuel line on my `32 . What was left of the original looked like steel to me. And also a rubber hose flex section between the engine and the frame, as "BJR" has said.
When I had my stint put in I asked them not to use red rubber line, alloy or copper, I opted for stainless cause I'm worth it and braided steel would look to streetroddy on my echocardiogram.
I've used it many times, but only in rigid applications never from engine to frame or firewall where there is relative motion. These are single flared and the fuel log is supported, never had a problem. I always keep an eye on the fuel system/lines no matter what they are made of, but then it's a hot rod, I'm under the hood more than behind the wheel.
I'd think copper might actually be better than steel in some ways, with brass even better yet, in terms of corrosion and exposure to fuel and contamination (water).The big Automakers have generally always used the cheapest materials they thought could get away with. Steel will work harden and crack too, that's why they use those vibration loops in brake line. I've noticed steel fuel tanks in old camp stoves and lanterns has lots of corrosion (rust) over time, brass is practically inert. Fuel tanks used to be coated with something called Terne, basically lead if I remember right. I'm sure that's banned by now.
I've never heard of copper bothering the fuel. What have heard and have seen is that copper can get brittle and break. That is usually where it is used on a long unsupported run where it can wiggle a bit. BchctyBob's short copper lines especially with the loops shouldn't give a problem but The guys who don't have the fuel block properly supported or have long runs that don't have support may have trouble after vibration works on the copper. The last broken one I replaced with steel was a run from the fuel pump to carb that looked like the guy had a 4 ft stick of copper tubing and no tubing cutter. No flair tool either as they had connected the ends with compression fittings and wound the tubing around to get it to fit. That one would never pass Hamb inspection even with the most liberal of the do it and get it done brigade.
If you drag race you can count on getting bumped from running your car with copper fuel line. I like the copper nickel idea and I'll probably give it a try at some piont.
I bet your boss has huge investments in petroleum companies. Using copper fuel line will increase the MPG so much that it will surely crash the world petroleum market. Best play it safe and use Nicopp.
I have used copper for many many years , Gas is ok diesel with sulfur is a no go . Copper is rated for the fuel pressure the normal fuel produces , along with compression fittings . I used Swedgelok fittings throughout my years at work with out one leak at pressures over 650 psi
The problem with most fuel line choices is what type of fittings you plan to use. To do it the best way is to use AN or JIC fittings and a 37 degree flare. That requires you to purchase a flaring tool that will do 37s.......not 45s. Compression fittings will work too, but are not really the best choice. Copper has more of a tendency to crack if much vibration is present. Steel or Stainless is the best choice but is somewhat harder to work with. Lastly, copper will tarnish and look bad. Usually the rewards of doing things the best way becomes a habit and pays dividends over time.
As far as original equipment is concerned, American car manufacturers have used: aluminum, brass, copper, and steel, and possibly other metals. Oldsmobile used copper as original equipment on their performance motors as late as 1966. Pontiac used compression fittings on some of their performance motors. Jon.
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