Fuel Pipe

[William2]

I am restoring an S4 Elan and fitting an alloy tank and complete new fuel pipe. Am I correct in saying that copper pipe is best for the run from the tank to the engine bay and then a short run of flexible fuel pipe to connect to the egine fuel pump? The tank connection is a threaded hole and I have purchased a matching threaded union and brass olive.

[billwill]

Not Copper, use Kunifer (cunifer) which is a copper-nickel alloy, though even for this there is some discussion that some fuels may affect it.

Copper can work-harden and crack rather too easily if there is any vibration.


See my Cunifer fuel pipe fitting starting about 3 messages down on:
lotus-elan-f19/getting-ogu-roadworthy-again-t26101-90.html


The only material that seems to be totally immune to modern fuels is nylon pipe, which seems to be the material of choice on modern cars. It uses barbed connectors and the pipe is forced onto the barbs with quite a lot of force.

[Quart Meg Miles]

Copper is also attacked by alcohol and is not allowed in aviation, I believe. Original pipes were nylon, weren't they, so do they need changing?

[Jeff@Jae]

The original nylon tubing is the best choice for ease of sliding through the chassis and corrosion resistance (they seem to last forever) but as noted in a previous discussion there is a worry should a fire erupt in the engine bay that OEM hose will be a liability. Stainless steel tubing perhaps ? With easily replaceable flex hose between engine and chassis ?

[TroonSprint]

I have used PTFE (teflon) pipe. It is flexible, strong, and is about the most inert material known to man.
Mike

[bluesbrother30]

I recently installed new solid line from the gas tank area through the frame and up to the standard fuel pump using metal brake line. I shortened a stick and put small flairs on each end where the rubber fuel lines joins......now wondering if this is a material that will withstand crappy California gasoline?? Should I switch to a stainless material?? Not fond of plastic or Teflon.

Mike

[billwill]

I recently installed new solid line from the gas tank area through the frame and up to the standard fuel pump using metal brake line. I shortened a stick and put small flairs on each end where the rubber fuel lines joins......now wondering if this is a material that will withstand crappy California gasoline?? Should I switch to a stainless material?? Not fond of plastic or Teflon.

Mike

Without saying what metal it is there is no way to know,

Rubber doesn't like ethanol either.

Was the brake pipe internal diameter big enough for a fuel line? Ordinary brake line as used on the Elan is too narrow.

You could try this: Put a clean sample of the pipe in a glass jar and fill with Eco fuel and seal it. If the liquid changes colour over a long period of time, it could be attacking the metal.