Best materials for replacing fuel hose?

I was crawling under by 47 year old Ford truck this past weekend looking for things that might need some maintenance attention now the weather is better, and decided it’s probably time to replace all the fuel hose. As the truck came from the factory, some sections of the the fuel hose are a flexible black plastic, and some sections are metal, presumably steel. Some rubber hose sections too. Any ideas about preferred materials these days to replace all that hose?

Rubber fuel hose should do the trick. The fuel system on that truck should be really low pressure, I’d think. The metal lines are probably used in areas that are, or could come into contact with heat. So I’d leave those metal lines intact if they’re in good shape.

I replaced the soft fuel lines on a 79 Jeep I owned. But I left the hard lines. Rust isn’t a huge concern in my area, so the hard lines were still in good shape. I had to replace the gas tank anyway, so I replaced all the soft lines from tank to carb. It seems like there were a few steel lines in the engine compartment, and the rest was rubber line.

Are you running ethanol gas?

If so, that’s what’s probably rotting out the fuel system.


I expect that is the most simple method , just standard rubber fuel hose for the flexible lines, and leave the steel lines in place. I was wondering if there’s some new miracle materials for fuel lines. For example steel brake lines are now often replaced with lines made with a copper/nickel material.

Most hardware, auto, or marine stores should have hose available for sale by the foot. Most likely all is now ethanol compatible, if the old hoses aren’t marked with OD/ID just take a section in with you. The plastic sections may have been molded to shape and are unlikely to be available, I would replace those too with flexible fuel line, but if they appear to be good, maybe not touch them at all.
And replace all the clamps.
Initially I read your post as a ‘47 Ford and got envious, then you made me do the math and came up with a ‘72…lol
Either are nice trucks.

Given the age of the truck, I’d say replace any of that plastic line as it is likely brittle. For reliability’s sake, I’d replace tank to fuel pump with a single length of 50 psi fuel hose. That means you only have 2 possible leak points. It also means your 3/8 ths ID hose won’t be restricted by any 3/8 ths OD (5/16 ID) metal lines. Protect any place that might get gravel damage with the corrugated plastic split-sleeve material normally used to gather and protect wire looms. Protect any hot spots with the silver slip-on thermal sleeve material from DEI or others.


The only plastic hose I recall ever seeing on old Fords was a tube used to protect metal hoses from rubbing directly against the top of the tank or on the frame. There was a section of rubber at every joint between sections of metal. And ethanol will cause a lot of problems with that old rubber. I’m surprised that fuel continues to flow through through after all these years.

Yep, it sure is surprising to me too. I’ve only replaced one 8 inch section of the fuel lines in all these years.

I was surprised to find flexible plastic line too. It is quite a long section, the fuel supply line most of the way from the main tank to the tank switching valve is plastic. Sort of a hard but flexible plastic. It’s getting a little too soft in places as you might expect. Maybe it is actually rubber but 47 years have turned it into plastic :wink: When I was fiddling with the fuel lines the other day I noticed the plastic line developed a kink just by me repositioning it for a look-see, which is one reason why I’m thinking to replace it all. The fuel return line is mostly metal for some reason, smaller diameter.