On Wed, 19 Sep 2007 16:29:37 -0700, Chuck Gould
wrote:

We don't know how old the poster's boat might be.
My 1983 boat uses copper tubing for all fuel and return lines.
Certainly doesn't and wouldn't use "pipe," but I suspect the poster
really meant tubing.

If I were building a new boat, I would use properly rated hoses rather
than copper tubing.

Our '81 GB has copper tubing in some places, approved hoses in others.
Not sure how it was originally equipped.