gofastwclass

iTrader: (2)

Disclaimer: I am merely sharing information I discovered or compiled. Fuel is highly flammable, EFI lines are under a lot of pressure (43 to 58 PSI or sometimes more) and I am not responsible if you are not able to get this or any of my other ideas I share on this or other sites to work. This method has worked for me in the past, however your mileage and results may vary. Do not try this at home, I’m a professional, wear your safety gear, eat your veggies, etc.

Now that we have the boring official stuff out of the way....
I recently completed a build and used OEM style nylon fuel line and fittings and wanted to share how it was done. I looked at the Dorman fuel line repair tool which comes in two variants, without fittings and with fittings. Nice, but at $96 and $230 respectively it was a hard pill to swallow for something I can't use regularly.

I realized these tools simply press the fittings into the fuel line and weren’t overly complicated. A bit of surfing found several solutions with varying degrees of success. The most successful of these used a caulking gun and bits of wood with notches and screws or a flare tool to hold the tubing but had no pictures. I’m here to fix that.

My method uses a caulking gun but it can't be the "normal" tray shaped variant, we need the one that only has two bars to hold the end on (very important), a giant nut I took from a hydraulic setup a friend had disassembled, a bit of scrap flat bar and a cheap flare tool.

This can be done freehand or on the car, but if you have the luxury placing it all in a vice works best.

I bought the caulking gun (HD138C) from Home Depot, but I’m sure Lowes has something similar. Remember it has to be the two bar type as pictured below. $13.


Normal boring parts store brand flare tool. $9
Big nut or short bit of 1 to 1.25” tube, etc. (this has to be large enough for the fittings to pass through). Free from scrap pile.
Short bit of flat bar stock. Free from scrap pile.
Short bit of steel fuel line with quick release end (optional). Free from scrap pile.


I welded the bar stock to the bottom of one of the arms on the caulk gun as pictured below to make a tab. I also welded a short bit of steel fuel line to the ram of the caulk gun to hold my fittings.



I use the big nut (or tube) to level the flare tool in the caulk gun and run the nylon tube through it.


The key to using this tool is absolute patience. If you rush the process you will crimp the nylon tube and the connection will fail. Start by cutting a test section of nylon tube with the sharpest box knife blade you have. The tube cannot be crushed, maimed or crimped and needs to be cut square. Insert this through the 3/8” section on the flare tool and tighten hand tight leaving about ¾” to 1” sticking out. If you have much more sticking out, the tube will want to fold over and kink. Place this into the caulk gun and place a fitting on the ram. Slowly squeeze the grip and align the fitting with the nylon line until they are perfectly aligned and touching. Once they touch and you are completely sure everything is aligned properly, slowly squeeze the grip and watch as the fitting is pressed into the tube. When you get 3/8” or so away from the flare tool, release the flare tool and slide it down a touch and continue the process until the fitting has been seated. Again, watch for kinks because if the line kinks you need to start over.


Once complete, you will be rewarded with a fitting that looks like this (depending if you use steel or nylon fittings). As you can see in the photo, the nylon does have a slight bit of abrading to it from the flare tool however these marks are not cuts, aren’t much different than the factory result and are hardly noticeable to the touch.




Parts list, prices and web links:
25 feet of Dorman (800-072) 3/8" nylon fuel line - $27
Qty 5 3/8" nylon quick connect fittings Dorman (800-082.5) - $15
3/8" steel quick connect fittings (what I used) – junk yard
Caulk gun (Home Depot HD138C) - $13
Cheap parts store flare tool - $9
Large nut or tube with ½” or better opening – scrap pile
Flat stock – scrap pile

i r teh noobz

iTrader: (4)

Nice work. Looks much easier than the "can of boiling water" method.

battsup

Looks good, I first saw this back in 2011 but there were concerns about damaging the fuel line using the caulking gun. I bought a Dorman 800-301 on sale for under $60, it's their fuel line repair tool intended for this purpose.

Here's where I saw it the first time: http://www.nastyz28.com/forum/showthread.php?t=220894

gofastwclass

iTrader: (2)

I was never able to get consistent results with the boiling water method.


Battsup, I never saw the thread on NastyZ28, oh well. His is the first one I have seen with pictures that worked. Worst case the info is mirrored here so more people have options.

Goldhawg

iTrader: (7)

Could you not use an arbor press with the same brake flaring tool? Seems like that would easier to maintain a straight shot. That is....if you had an arbor press

tracetrimble

Just wanted to add another option to this great idea. Here is what I did differently, and it works great.

- Saw a Ø2 1/8" hole in a 2x4, just for the slug.
- Drill out the center pilot hole to Ø5/16".
- Carefully saw the slug in half. I used a hand saw and a vise - clamped the slug in the vise first to get the cut started until it started to bind, then finished the cut with the saw clamped in the vise and raking the slug over it.
- You now have two clamshells that fit around the hose, and inside the caulk gun.

Then all I had to do was use a hose clamp around the assembly, and clamp it as tight as needed to prevent slip. This contraption doesn't seem to leave marks on the hose, either. This worked well for my caulk gun design and what I had laying around. I also removed the retainer clips before pressing the fitting to keep from damaging them. Hope this helps!

L92 OLDS

Thanks for sharing. The abundance of parts in the salvage yard and the fact that they are a lightweight, safe OEM design make this a no brainer. There are a lot of companies out there gouging everyone for their anodized fittings and adapters.

33willys

iTrader: (1)

After years of using 3/8 inch brake line and f.i. hose I decided to try nylon lines on my latest build. I got the Dorman tool for under $60 plus 25 feet of 3/8" nylon and 25 feet of 5/16" nylon. I also prefer the GM factory steel fittings and the security clips too. The Dorman tool worked very well with the 5/16 line but ran out of horsepower on the longer 3/8" line. To firmly seat the last 3/8" or so I used an arbor press which was a snap to use. If I were to do very many this is the way to go. One thing that wasn't mentioned is to use a drop of oil on the fittings when pressing them on. Bottom line with using nylon line is it doesn't cost any more than other lines (maybe even less than some), is easy to work with, not affected by gasoline additives and easy to route.

tracetrimble

Yes, I did apply a little Vaseline on the fitting and hose opening before I pressed them. Probably helped, and typical practice if you're used to working with stuff like this. I really floundered over doing all the 6AN conversions and hard pipe since that seems to be the norm, but it would be considerably more cost and leak points. We shall see...

slofut

Guys,
I'd like to hear a follow up on this thread now that it's been 9 months along. Are you still happy with the Dorman vinyl fuel line? How about the connectors? Any o-ring problems, or trouble with fittings or line? Need to pull the trigger on a way to do my c3/ls1 tank and regulator filter. I wish there was a way to use this line with the aluminum 6an fuel rail adapters that have the screw on retainers.
Any advise?

G-Body

iTrader: (4)

33willys: I also had an issue with my dorman tool running out of power and not being able to push the 3/8" fittings all the way in. The lock for the lever would begin to slip. Eventually the handle cracked, but luckily the distributor I bought it from said it was lifetime warrantied.....they sent me a new tool out and it is amazing, works much better than the first one. Has no problems seating the 3/8 fittings.

slofut: No issues with any of the fittings or line. Even on the fittings that I installed manually before I had the correct tool.

ryeguy2006a

iTrader: (27)

I used the same method in 2012 with my 1976 Trans Am, and it is still running strong with no issues. The nylon lines are very easy to use. I wrapped about two loops of electrical tape on mine where the flare grips the line and it will eliminate the marring left from the flare tool.

I plan to use the Nylon lines on my current build as well. Although fuel injected engines were never in the older cars, I like how they give more of a factory appearance.

truckdoug

iTrader: (25)

i am gonna try this out on my next swap. i'm sick of shelling out for AN fittings.

zebrabeefj40

I can't speak to using the Dorman line on a gas car but I did replace all the fuel line on my diesel Ford F250 with Dorman line. The Ford used a combination of nylon, steel and rubber line from the dual tanks to the motor. My brother and I replaced the nylon/steel combination lines with nylon to eliminate some of the joints. 6 years later and all is still leak free. We did protect some of the nylon with split loom where it went by potential sharp edges but other than that we did nothing special.


Nick

gofastwclass

iTrader: (2)

This stuff flat out works. GM uses it, what else do you need to know? I have used it on multiple friend's cars and my personal vehicles including my ever reliable daily driver / winter beater Thunderbird which has been documented on this forum. I just looked at the odometer yesterday and think I'm around 70,000 miles since the conversion on the Thunderbird.

01cherryreds10

iTrader: (9)

Is there a way to form bends with this stuff like the factory? Heat it and bend?

gofastwclass

iTrader: (2)

I think that is what needs to happen, but there seems to be a narrow window of heat to melt ratio. I never got it to work consistently but I didn't invest a lot of time on it since I didn't have an accurate method to measure and control the temperature.

Tight bends are the main reason I use NiCopp so much for the long runs and nylon for the flexible bits. Look for CNC625 on Amazon, it's $56.xx with Prime. That is 3/8" x 25' which works out to $2.2x per foot.

33willys

iTrader: (1)

I used nylon lines for my catch can and required 90 degree bends. The required lines were short so I filled the nylon line with sand, capped both ends and used a heat shrink gun to SLOWLY bend the line. Once bend I held it for a short period and it remained bent with no crimp or melt. May be able to use water in the line with the same results but capping would be a bit harder.

Project GatTagO

iTrader: (7)

How do you make tight 90 degree bends with NiCopp? I tried this and only got a bunch of kinked line. I suspect I have a shitty bender. Any suggestions for a quality bender?

Andrew

truckdoug

iTrader: (25)

are you guys putting a GM bubble flare in the hardline to connect the push lock fittings to?