Replacing late model fuel injection fuel lines
 

I need to replace some rusted FI lines and some nylon lines and fittings that broke when I tried to take them apart. Some of the lines are nylon and some are steel.

I think I can get the replacement fittings and nylon line, but if someone knows of a good discount source please advise where. I would also like some guidance on how the fittings are supposed to be installed onto the nylon lines. Do I just use brute force to push the lines onto the fittings? Should I heat the lines first? If so, how and how much? Any other tips/tricks?

I think the metal lines will be harder to replicate. They appear to be made of normal steel but have a ridge on them about 3/4" from the end. I can bend steel line, but I have no way to replicate the ridge. I might be able to convert these to rubber or nylon lines, but I will need to have the "ridged ends" to attach them to fittings that are on the vehicle. Any idea where to get the ends or is there a reasonably priced tool that I can buy to form the ridges?

Any websites with info on this?

Maybe Inline tubes can fabricate those lines.
Dorman offers those repair fittings and nylon line. They offer the tool that inserts the fittings in the lines, But it is expensive.
I have seen the repair kit offered on E-bay.
http://www.dormanproducts.com/catalo...Disconnect.pdf

I do not know what vehicle you are working on..
FWiW
I recently replaced the lines on my 93 k 3500. Its a tbi and has the metric threads. Summit and jegs have adapters to convert late model fi to an style braid or inverted flare.
I used adapters to go from factory to an to hard line. It worked good for me and was not that expensive.
HTH

Thanks for the link and replies. Those are the fittings that had found.

I am working on a 2000 S-10 Pickup and would like to keep the cost down as much as possible.

I have seen(online) the tool for inserting the fittings in nylon tubing and I think/hope I can rig something up to get the fittings inserted.

The metal lines with ridges near the ends appears to be more of a challenge.

I have a 96 s-10 (v6) with central sequential fuel injection. It has the fuel line that goes into the regulator much like what you describe. This year has only metal and the lines go to the back with a bracket and a threaded connection back by the distibutor. I am pretty sure they are metric threads with the coarse (1.50) pitch. They use them a lot on GM's and adapters are available for this connection.
Maybe you could get one this style from a junk yard? This style has the injectors in a six pack with the regulator and the tubes that go down to each cylinder. (not my favorite design)

Is the line you have completely wrecked? If the end that goes into the injectors is still good? You may be able to just attach to the other end.
Have you used the Army/Navy fittings before? They are good enough for airplanes and helicopters. Nice stuff but a little hard to get together and can handle some high pressures.

A picture may help us see what you are dealing with... It is just a fuel line and it is high pressure (60 plus psi) but people do fabricate high pressure fuel lines like in a retrofit FI set up.


I had a firebird that a previous pump replacement person had cut an access hole and severed all the sending unit lines. I could not find a used one that was not worse than mine. (mn rust) I took it to a radiator guy and he soldered some tube unions on them. It worked great and only cost $20. That was on a TBI so a lot less pressure but I think you get the idea.


Sometimes I have to make what I need because the parts are not available or way to much $. I guess what I am saying is a little creative thinking can go along way...

It is not like the factory set up is all that strong either... It is just plumbing...:D

As far as I can tell, the lines at the injectors and directly off of the engine are OK. It is the 3 lines that go from the fuel filter area (under drivers door) back to near the tank, and then there are 3 short lines than go tothe tank or vapor canistor.

The short lines in the back are primarily nylon lines with fittings and I think I can replicate these. One of them has a short piece of steel in it, but I think I can redo it with just nylon line.

It is the 3 metal lines that run on top of the frame rail from the fuel filter area back to near the tank that I am trying to figure out how to replace.

I see, on my 1 ton I used 3/8, 5/16, and1/4 break lines and unions from the local napa to cover those.

The fittings you are talking about are called a Saginaw flare and they use a metric thread with an O-ring in front of the ridge as a seal. Dorman sells a repair kit with a ~ 12" section of 3/8 inch line with the the nut, flare and O-ring, the repair is spliced into the exsisting steel line with a compression fitting union (supplied). I believe a 5/16 repair kit is also available.

^^^^^ I did that with my '88 work truck.

Then I bought the fancy flaring tool that reproduces the ridge in ordinary 5/16 or 3/8 tubing.
http://www.mastercool.com/pages/flaring_tools.html

Schurkey, looks like an awesome tool, but I'm not sure it fits into the reasonably priced category.

I have found it online for $310.00 and although that is a lot I may actually consider it as it does look like it works very well.

Any issues with it, or is it as great as it seems?

Are there any cheaper models that will also do the GM fuel line ridge?

Any other models/brands that anyone would reccomend over this one?

I have one too . I used it for shop use and for making my own stuff, no problems in the last several years I have had it and the dies are not that expensive either , I originally bought mine when I found out gm discontinued fuel lines for the 96-2000 pickups and mine sprung a leak, choices where let the truck sit or make new lines , mines a half and half system , half braided and half hard line , braided tank to filter ( where it rotted out before ) and stainless hardline from the flex coupling at the filter to the base of the manifold . oh and if your going to put in stainless this is the only way your gonna flare it as the stuff is hard to flare . the gm o ring fittings come out great on the 1st or second try if you follow the directions , as for the nylon lines you heat them up in super hot water ( about 180*) to soften them up and slide them over and let them cool .

Yup.

Keep looking, you may find a better price.

Single drawback: You have to pay extra to get the 37 degree flare dies; and there's no place to store them in the original plastic box.

This is the BEST solution for "committed DIY" or low-volume production.

thanks, stumpy.
For the suggestion of heating the nylon lines in hot water to insert the fittings. I wondered how this could be done without purchasing the Dorman tool.

Has anyone used the S.U.R.&R. fuel line repair fittings.

They seem to be an alternative to the Dorman fittings and don't require any special tools to install.

I'm considering several options, but one is to replace all of the steel lines with nylon using the S.U.R.& R fittings/adaptors. Any reason that would not be a good option?

I wouldn't use the nylon other than for short distance flex connectors ( under 18 inches) and in sheilded positions , as they get brittle with age and don't like it when they get hit by stones, they split when flattened ( flatten a straw and see what happens as a demonstration )thats why they use steel for the long and open runs . this is why I used the braided lines to get away from this ( IMO ) garbage as I have had a Nylon hose split underhood on a firebird and caused a fire , the fittings are availabe from earls you have to look for them as they are not what you think they are also I converted my fuelfilter from the gm push spring ring to a threaded one as around here the dirt gets into the rings and makes them almost impossible to remove .

I ordered one of the MasterCool 71475s and it arrived today.

I tried doing some practice flares on some 5/16 steel lines.

I got a perfect 45 degree double flare and push lock flare on first try, but after about 10 tries I have not yet produced a good GM Fuel Line Flare. It forms the "ridge" but it also bulges the line in front of the ridge and 2 or 3 times it was not uniformly bulged.

Any tips/suggestions on how to make the GM Fuel Line Flares?

I tried it on the NiCopp line and got a perfect GM Fuel Line Flare on the first try. This will take care of the project at hand, but I would still like to understand why I could not get a good flare when I tried it on the steel line.