What are your thoughts on nylon fuel line

[holyford86]

Did a 4.0 swap about 10 years ago and plumbed everything with rubber fuel injection hose, I've been thinking about replacing it with OE style nylon line and push connect fittings as I can borrow the tool to properly assemble the lines. I feel like it's a better choice than using rubber lined AN hose, and my pockets aren't deep enough to justify the better, ethanol resistant stuff and all the adapter fittings I'd need to make it work right. Thoughts?

 

[dvdswan]

Do you still have the steel lines or did you replace those with rubber as well? When I installed my 5.3L I used 3/8" and 5/16" steel lines along the frame, then areas where a connection was needed I used the AN fittings and a 1' long braided line. It's hard to see but on the top of the driver frame rail is a single line that comes from between the dual tanks.

 

[holyford86]

Do you still have the steel lines or did you replace those with rubber as well? When I installed my 5.3L I used 3/8" and 5/16" steel lines along the frame, then areas where a connection was needed I used the AN fittings and a 1' long braided line. It's hard to see but on the top of the driver frame rail is a single line that comes from between the dual tanks.

Yes, I used the lines from the donor as far as the braided lines from the fuel rail and the stainless lines between those and the fuel filter, but needed to attach them together with rubber lines because the flexible portions were damaged and living in the rust belt makes it difficult to find any that aren't trash. I also deleted the dual pump system and the canister found on the first gens and went with a high pressure in tank pump also, thereby making the factory nylon plumbing useless also. I would like to stay away from using steel line to replace the rubber because of the possibility of rusting and don't feel like dealing with that in a few years either, haha.

 

[Sharky]

make sure to use up to date fuel injection fuel hose, it wont rot from the ethanol & other additives in todays fuel.

 

[Shran]

I would be awful tempted to use stainless brake/fuel tubing or normal steel brake line as a close second option. I'm not a huge fan of long runs of rubber hose and nylon is OK but not as easy to repair, IMO. I have a bunch of rubber line on three of my trucks and it really bothers me, it was supposed to be a quick and dirty fix and I never ended up replacing it.

 

[dvdswan]

I used 25' - 3/8" stainless tubing and 5/16" for the return

Amazon.com: 4LIFETIMELINES 25 ft 3/16 316L Marine Grade Stainless Steel Brake Line Replacement Tubing Coil and Fitting Kit, 16 Fittings Included, Inverted Flare, SAE Thread, 0.028 inch wall thickness : Everything Else

 

[Uncle Gump]

I just bought the doorman tool to do nylon.

I guess that says where my head is at with fuel lines.

 

[Snoranger]

Nylon fuel lines will last longer than the frame in the rust belt.

 

[mikkelstuff]

I think the nylon or whatever fuel lines are crap. No fuel line should be that difficult to patch or join.

Decent rubber fuel injection hose is readily available. Steel lines are also great.

 

[Uncle Gump]

I think the nylon or whatever fuel lines are crap. No fuel line should be that difficult to patch or join.

Decent rubber fuel injection hose is readily available. Steel lines are also great.

My 36 year old Bronco II still has the original nylon lines. How crappy can they be?

 

[holyford86]

make sure to use up to date fuel injection fuel hose, it wont rot from the ethanol & other additives in todays fuel.

I am currently using the up to date stuff but all rubber hose has a lifespan, and that lifespan is shorter than one may think in some cases, hence the want to stay away from it.

I would be awful tempted to use stainless brake/fuel tubing or normal steel brake line as a close second option. I'm not a huge fan of long runs of rubber hose and nylon is OK but not as easy to repair, IMO. I have a bunch of rubber line on three of my trucks and it really bothers me, it was supposed to be a quick and dirty fix and I never ended up replacing it.

I've considered using stainless tubing but it's a pain to work with in the limited space I have and it would bother me if it looked like crap, if I was doing a new build and had the body off it would be the ideal thing to use though. I'm in the same boat, was supposed to be temporary but has proven to be permanent thus far. The truck isn't anything super special to anyone but me but I'm not a fan of preventable vehicle fires either.

I just bought the doorman tool to do nylon.

I guess that says where my head is at with fuel lines.

My employer has it and I'm free to use the tool whenever, so I guess my head is in a similar place, haha.

Nylon fuel lines will last longer than the frame in the rust belt.

In my case the inverse has proven true, but if I hadn't changed everything they'd still be there. 412k on the frame so far and it's only had two small patches done where the shock mounts live.

My 36 year old Bronco II still has the original nylon lines. How crappy can they be?

My point exactly. I've dealt with rusty trash fuel lines on GM stuff a third of my truck's age many times, I don't like doing it any more than I need to.

 

[Uncle Gump]

I just started my fuel line rework. The Dorman tool works with ease. It's warm today and didn't even use a heat gun. Pushed it right together.

I did notice on the truck the supply line switches from 3/8 at the tank to 5/16 leaving the canister filter. And the return line does the opposite. So this kit I bought doesn't nhave reducer fittings. So it looks like I'm gonna need two reducers to finish the lines up. They have nothing local so it's back to the internet...

 

[Uncle Gump]

So out of all this... I still need two fittings.

Across the bottom are different repair unions... repairs on nylon are easier now then they use to be.

 

[Uncle Gump]

The newer Dorman connectors also have an improved retaining clip... opposed to the old hairpin style.

 

[holyford86]

I just started my fuel line rework. The Dorman tool works with ease. It's warm today and didn't even use a heat gun. Pushed it right together.

View attachment 78962

I did notice on the truck the supply line switches from 3/8 at the tank to 5/16 leaving the canister filter. And the return line does the opposite. So this kit I bought doesn't nhave reducer fittings. So it looks like I'm gonna need two reducers to finish the lines up. They have nothing local so it's back to the internet...

I've got access to the same kit, the fittings are slightly different but still a big improvement over the factory stuff, I think this is the direction I'm going to go in. Surprising you can't find the fittings you need locally, everyone around here sells the fittings for nylon.