Hey all,

I'm sure this has been covered before, though can't seem to find the specifics. I have a 92' F250 7.3 idi and plan on replacing my fuel and return lines to my primary tank (forward mid-ship tank) as my fuel lines are too rusty to salvage. Completely disconnecting the aft tank. I've dropped the primary tank and am installing a new sending unit and a new Facet lift pump as well.

I know I'm going to catch hell for this, but I wanted to replace the steel fuel lines with rubber hoses instead. I live on the Hawaiian coast and the rust is impossible to keep up with. I understand the issues, but If I take care in installing the rubber hoses with protective sleeves (for heat and rubbing) while using 'P' clamps then I don't foresee any issues, unless there is something I'm completely missing?

I'm also trying to lock in the exact fuel lines ID sizes used. From what I can find, the fuel hose ID's seem to vary from 1/4" to 3/8" for this engine/year. I understand that the fuel hose is a different size than the return.

If I do wind up using rubber hoses, does anyone know what sizes I would need? My sending unit hasn't arrived yet, so I can't go off of that and my old one is too rusted to get an exact measurement off of.

 

Supply is 3/8" and return is 5/16".
1/4" might be for the return lines from the Injectors on the 7.3 IDI.
So the 92 yr model used steel fuel lines instead of the plastic one`s?

My 86 uses plastic tubing from both tanks to the FSV, then plastic forward a ways
and connects to a steel line. Then a rubber hose up to the Water separator/filter,
then loops back down to a steel line under the engine over to the Lift Pump.

4 years or so back I swapped the rear 19 for a 38 gallon tank. I replaced both senders and Shower Heads.
I covered the top of the Senders with Anti-Seiz thinking it might keep the tops from rusting.

Had problems with the FSV this summer...long story.
I now run rubber hose from the rear tank to the engine and back.
Iam using the front tank for a transfer tank, to pump to the rear, and going to use the Facet electric pump.
Just don`t have the electric connected to the pump yet.


Charlie

 

Yes, that sounds like the same set up I have. The supply line from the tank is plastic, to steel, to rubber up to the filter. My FSV crapped out as well. One tank, less problems now. I do like the idea of making your forward tank a transfer tank...clever. Not sure how long the rear tank has been nonoperational (due to the FSV not working...bought it that way), so not sure what to do with that thing...

Thanks for the info though!!! Very helpful again...

 

You can buy aluminum or even stainless fuel lines that are far less likely to have corrosion issues. I have heard stainless is harder to work with, but aluminum is very easy and you can even rent all the flaring tools and what not from your local auto parts store. I personally wouldn't convert from hard to soft lines, with that being said i don't think my High-boy with 3 tanks has a single hard line and it's never had any issues.

 

I don't see any problem with that plan. FWIW, as far as I can tell the steel lines were used primarily for ease of assembly rather than any inherent performance characteristics. Good call on the "p" clips, sounds like you've really thought this through.

Having 2 tanks is nice for sure, but I always wondered why they didn't just run a rubber hose between the bottoms of the 2 tanks and call it a day. Heavy trucks use that setup and it works great, no valves and switches and BS to fail. If you were having problems with that stuff (very common, many do) I can't blame you for ripping it all out.

 

Parts stores sell Ni-Copp line in 3/8 size, price may not be fun tho so check online as well. This matetial ain't never gonna rust away and it's stupid easy to bend (well the 3/8 is a bit tricky as it wants to kink instead), it's what shops have been using for brake lines for ages now instead of steel. The IDIs fuel lines are under vacuum between the tanks and the lift pump, so zero flaring is needed on the lines (good thing if you go with stainless lines, they are the devil to flare), just use good clamps. Return lines are 5/16 from the junction block on top of the engine down to the tanks, there's zero issue with replacing that whole section from the engine down to the FSV with rubber hose. Just make sure to use good hose, SAE 30R9 (typically sold as fuel injection hose) actually handles diesel fuel pretty well, tho I personally prefer transmission oil cooler (TOC) hose cause it's usually thicker walls so better abrasion protection and much higher temperature rating.

 

I plan on using this:

https://www.eaton.com/ecm/groups/pub...t/pll_1173.pdf

Get lines cut at a heavy-truck repair shop.

Roy

 

Those look pretty great yes.

 

I will go to a heavy truck repair shop...get them to make up Eaton lines which terminate in hose barbs. So, my lines will be 95% that Eaton stuff and the rest normal rubber fuel line.

 

Isn`t the Eaton Fuel line plastic line?
Nothing wrong with plastic line, big rigs use it for the Air Lines also for the Brakes system.
probably comes in a role in a box, it will have to be straightened out, and probably some
heat applied to make the bends you need.

Dorman makes the push on fittings like go on the Senders at the Tank and FSV.
And also push on splices.
Some how my supply line from the rear tank came out of the Frame Clip, and was hanging
down to where I guess it got pinched between the Axle and Bump Stop. used a Dorman
Splice and a section of fuel line I got from PNP. Worked great.

I guess it was back in June I was messing with that %#@&% FSV, it was pulling from rear
tank and returning to the front tank. Eliminated the FSV and tried to splice the plastic lines
with the Dorman Connectors. Could not get them to quit dripping. So pushed 3/8" rubber
hose onto the plastic line. But it does not go into the hose very far, I clamped it on and so
far, so good. It is not under pressure, just suction. But could be a cause of air into the system
if the rubber shrinks with age.
The return line is no big deal, not under pressure.

Some Rubber fuel hose can get pretty pricey.

There are YT Video`s showing how to heat the plastic line to push the barb fittings on.
Also there are tools to shove the 2 parts together, but pricey.
And other DIY ways.

Just thought I would throw out my thoughts and trials and tribulations,....


Charlie

 

Yes, the Eaton is plastic. It is formulated to carry Diesel. And, it comes in more- and less-flexible versions.