Replacement fuel lines

[SETOYOTA]

Looking at replacing the copper lines on one of my trucks. Searching through the forum there is a lot on replacing return lines and the use of nylon air lines .

Any opinions on what is best to use in replacing the main supply line from the tank? Can you use a 3/8 line to replace the 1/2 inch.

What about the fittings / hose ends. Starting at the fuel tank .

 

[rustystud]

Looking at replacing the copper lines on one of my trucks. Searching through the forum there is a lot on replacing return lines and the use of nylon air lines .

Any opinions on what is best to use in replacing the main supply line from the tank? Can you use a 3/8 line to replace the 1/2 inch.

What about the fittings / hose ends. Starting at the fuel tank .

I used "PTFE" stainless steel lines from the tank to the filters. Then 3/8" DOT poly lines to the injection pump and for the return lines. You could just use 1/2" DOT poly lines from the tank to the filters and then 3/8" DOT poly to the injection pump. All the modern semi-trucks and all our buses use DOT poly lines. Have for decades now. I just used the PTFE stainless steel lines for added insurance in case some branch or something snagged my lines. They are extremely strong, and with the added "hard wrap" I put around every hose they should never break, corrode, or work harden.

I forgot to mention, if you go the "DOT poly hose" way you will not need to buy new brass fittings as they are the same. You just will need new "ferrules" and "inserts" .

 

[SETOYOTA]

When I see the term ferrule I think of the compression ring you put on hose when using those fittings . Please forgive my ignorance but what do I need to use on the poly tubing or atfe tubing to actually connect it to the fittings on the tank and the filters? Are there flared inserts that go into the nylon or is this something you have to make? Or is there a new connector I need for the tank etc.

how do you connect nylon hose to a inverted flare connector?

 

[rustystud]

When I see the term ferrule I think of the compression ring you put on hose when using those fittings . Please forgive my ignorance but what do I need to use on the poly tubing or atfe tubing to actually connect it to the fittings on the tank and the filters? Are there flared inserts that go into the nylon or is this something you have to make? Or is there a new connector I need for the tank etc.

how do you connect nylon hose to a inverted flare connector?

I discussed this before here https://www.steelsoldiers.com/showthread.php?155917-Replacing-copper-lines-with-DOT-poly-air-hose . You will need the "ferrule" and the "insert" . I forgot to mention the "insert" in the last post.

 

[Floridianson]

I don't believe you can go from inverted flair to compression fitting just by changing out the insert, ferrule and crush cap. The inverted flair does not use those fittings and with internal threads big difference. When I do change out to Synflex dot air line when bypassing the FDC I just buy the dot new fittings or use the collection I have in the tool box as they have the correct crush sleeve. If I remember correct the Deuce tank has inverted flair coming out and the primary fuel filter has inverted flair on both sides. Here is the a pic of DOT compression fitting I had in the office sitting around. When I tighten down the Synflex crush sleeve when it seems to get tight I go even farther till it just about bottoms out on the fitting. We have to get a good bight on the plastic tube I believe. Myself I would run 1/2'' all the way to the booster pump. With compression fittings seems we loose ID because of the insert fitting and that does not happen as much as inverted flair. I have been to your house and seen your toys so I know you can afford to buy any little fitting if you need them.

 

[SETOYOTA]

The problem is I don’t know what to buy or where to get it.

 

[Floridianson]

My NAPA carries it. As I said above I don't think we should choke down the size leading up to the IP booster pump so 1/2 all the way. I don't see any problem with the copper line that is there leading up to the primary. It is tucked into the frame well. It's the copper line that runs under the frame rail from the primary fuel filter to the booster that could lead to a smash. One would think if you just got some thick wall copper tubing and ran a new flared line above the frame it would be fine or just 1/2 Synflex from the primary out to the booster.

 

[Jbulach]

Search ebay for “1/2” dot air brake fitting”, for fuel stay away from push-connect and any fittings with plastic parts.

 

[SETOYOTA]

I suppose what I need to start with is replacing the elbow fitting at the tank with one that is a non inverted flare. Next would be nylon line with proper ferrule and insert for the new fitting . This same process would also need to be done at the primary filter as I believe the connection is an inverted flare as well.

 

[Floridianson]

Yep primary is inverted flair.

 

[rustystud]

I don't believe you can go from inverted flair to compression fitting just by changing out the insert, ferrule and crush cap. The inverted flair does not use those fittings and with internal threads big difference. When I do change out to Synflex dot air line when bypassing the FDC I just buy the dot new fittings or use the collection I have in the tool box as they have the correct crush sleeve. If I remember correct the Deuce tank has inverted flair coming out and the primary fuel filter has inverted flair on both sides. Here is the a pic of DOT compression fitting I had in the office sitting around. When I tighten down the Synflex crush sleeve when it seems to get tight I go even farther till it just about bottoms out on the fitting. We have to get a good bight on the plastic tube I believe. Myself I would run 1/2'' all the way to the booster pump. With compression fittings seems we loose ID because of the insert fitting and that does not happen as much as inverted flair. I have been to your house and seen your toys so I know you can afford to buy any little fitting if you need them.

OK, it seems I misunderstood the original question. I thought he was eliminating all copper tubing. Now there are a few "Flare" fittings that will need adapters to the DOT tubing, but most of the copper lines are not flare type. The fuel tank connector is an flare fitting and I had to buy a special fitting from "Parker" for that. Most all other fittings are going to NFT pipe fittings so the standard fittings will work.

 

[rustystud]

The problem is I don’t know what to buy or where to get it.

Parker will have all the fittings you will need.

 

[Floridianson]

Yep just the fuel line from the tank and primary is a flare. Really it's not a inverted flare just a simple flare. Inverted flare is like brake line the has the first flare folded in then flared out or double flared. Maybe they went with the easy way to fix with a simple flare tool you can repair the fuel line. Yep the rest of the copper air line are compression fittings. Having my own trucking /excavation company with trucks that had to meet DOT regulations we would never use anything but DOT stamped stuff when air replacing fittings. That habit just carries on now so I don't try and skimp on the parts or go to Home Depot for my parts.
Yea I am getting old and have to read things twice but the picture also helped show the flare fitting. Pictures good, fire bad. Me strong as bull smart as tractor. The picture shows how the DOT fitting has a good ridge on the ferrule and a flat ridge on the inside of crush collar. Looks like the pic with the copper line and long neck crush collar cap uses just a rounded ferrule and the crush cap to match. We don't want to use that set up on Synflex or polly line.

 

[SETOYOTA]

Other than cutting off the copper line after the tank connection and using a compression fitting to attach a nylon line I don’t see how to replace the main supply line with the DOT stuff . What sort of fitting and where would you get it to replace the one on the tank?

 

[rustystud]

Other than cutting off the copper line after the tank connection and using a compression fitting to attach a nylon line I don’t see how to replace the main supply line with the DOT stuff . What sort of fitting and where would you get it to replace the one on the tank?

Like I said earlier, Parker Hose will have all the fittings you will need.

 

[SETOYOTA]

Would you have a picture of what I’m looking for? To replace the large block fitting. Parker has thousands of fittings but I have not seen anything that will work. I suppose I can take the pump apart and investigate further.

 

[Floridianson]

I googled it and also went to parker for you but I did not see them. Maybe Rusty can show you the correct page and fitting number from Parker?

 

[pjwest03]

Fitting

Would you have a picture of what I’m looking for? To replace the large block fitting. Parker has thousands of fittings but I have not seen anything that will work. I suppose I can take the pump apart and investigate further.

Along the lines of what Rusty was talking about, 3/4-18 inverted flare to PTFE hose: https://www.summitracing.com/parts/aer-fbm1139/overview/



And the corresponding hose: https://www.summitracing.com/parts/aer-fcc0820/overview/

 

[SETOYOTA]

That looks close but the flare end would need to be threaded to go into the block on the tank

 

[jbayer]

It is. Right side of that fitting.