The Stovebolt Site Forums The Shop Area Engine Shop fuel line question...what material can I use?

Do I have to use steel tubing for the fuel pump to carb connection? Can I use copper? The only reason Im asking is, I have some copper tubing that is the perfect size. I appreciate your response. Thanks!

That would be fine. If you want to get fancy chrome water supply line works great also.

I once used a copper line to make a "cold can" to try and relieve my vapor lock problems on a truck I used to have. When I told my mechanic friend about it, he told me that the gasoline would eventualy eat through the copper. Anyone else know if that is true?

From
http://www.faqs.org/faqs/autos/gasoline-faq/part1/

"Gasolines are usually defined by government regulation, where properties and
test methods are clearly defined. In the US, several government and state
bodies can specify gasoline properties, and they may choose to use or modify
consensus minimum quality standards, such as American Society for Testing
Materials (ASTM). The US gasoline specifications and test methods are listed
in several readily available publications, including the Society of
Automotive Engineers (SAE) [38], and the Annual Book of ASTM Standards [39].

The 1995 ASTM edition includes:-
D4814-94d Specification for Automotive Spark-Ignition Engine Fuel.
This specification lists various properties that all fuels have to comply
with, and may be updated throughout the year. Typical properties are:

...4.10.5 Copper strip corrosion
Ability to tarnish clean copper, indicating the presence of any corrosive
sulfur compounds

4.10.6 Maximum Sulfur content
Sulfur adversely affects exhaust catalysts and fuel hydrocarbon lead response,
and also may be emitted as polluting sulfur oxides.
Leaded = 0.15 %mass maximum, and Unleaded = 0.10 %mass maximum.
Typical US gasoline levels are 0.03 %mass. "

So today's gasoline should not affect the copper line.

Copper is subject to metal fatigue, though. That's the main reason steel is used. Copper lines of any significant length will crack over time.

You can use brake lines they come in several diameters and it is mor forgiving than the hard steel.
Just make sure you have a flexible fuel hose from where the hard line leaves the frame to where it hooks to the fuel-pump.It needs to be flexible so it does not break when the engine torques/twists.

I'm sure that some one will tell me GMC did it different to Chev , but on my truck , the original steel lines are still in place , with no flex line anywhere.
Copper work hardens real quick . I used Copper on the bypass oil filter lines and the drain line broke after 2 yrs of daily driving .

I've had the same copper 3/8th fuel line from my fuel pump output to the 390 Holley inlet, for better than 25 years on my 292. Still no problem. [It's connected w/ 3/8 rubber fuel hose 3" from fuel pump and goes into more rubber fuel hose and a G15 gas filter before the carb. -- that probably negates vibrations]
I'll let you know when it fails me.
In fact, the rubber hoses and fuel filter I just replaced today (about every 2 years or 10,000 miles.)