Hate that these little things keep holding me up but they are. I'm wondering why is fuel leaking from where the arrow is pointing in the picture below everything is tight. Its a new line I can't see anything wrong what could be the problem? Thanks, Joshua
Bad seat in the brass fitting? Cracked line at the flare? :-\
Quote from: Big Fins on May 17, 2025, 05:19:03 PMBad seat in the brass fitting? Cracked line at the flare? :-\
Like the elbow could be bad? Or could the line not be getting seated properly? Is that even possible i swear these things always seam to just work
Is that the correct male fitting? Maybe it's just the angle in the pic, It looks different than what I'm used to seeing, at least on late '50's-early '60's cars, where the fitting appears "beefier" and the flare seats against the threaded end. Here's an example.
The elbow should be an inverted flare and the line should be a double flare. Any chance you can take the connection apart and show a picture of both pieces? Harry
Either a poorly done flare, dented in the connection or maybe just not tight enough
Greg Surfas
Quote from: harry s on May 17, 2025, 06:23:40 PMThe elbow should be an inverted flare and the line should be a double flare. Any chance you can take the connection apart and show a picture of both pieces? Harry
Here the package of the elbow i bought, I can show the connection apart tomorrow morning
The packaging costs more then the contents. I remember when a parts store had a huge "Weatherhead" cabinet with every sort of brass fitting and coupler to be imagined. Now, each fitting is sold separately and is cheap soft brass.
It's hard to tell for sure by the package. Harry
Quote from: harry s on May 18, 2025, 08:26:51 AMIt's hard to tell for sure by the package. Harry
Got those photos maybe this will help figure out why its leaking? Any help is appreciated Thanks
That should be the correct fitting and I have used stuff from that brand before and not had any issues or concerns. Looking at the photo it does look slightly odd but it could just be the angle of the photo. The line end also looks strange to me too like there is kinda of a point at the edge of the taper.
Do you have a flaring tool? Maybe stick it in the line and see if it looks and different after you try and give it a bit of a re flare?
Is that just standard plumbing soft copper? Or nicop brake line? Did you make the line or buy it pre made for this application?
Quote from: TJ Hopland on May 18, 2025, 02:47:00 PMThat should be the correct fitting and I have used stuff from that brand before and not had any issues or concerns. Looking at the photo it does look slightly odd but it could just be the angle of the photo. The line end also looks strange to me too like there is kinda of a point at the edge of the taper.
Do you have a flaring tool? Maybe stick it in the line and see if it looks and different after you try and give it a bit of a re flare?
Is that just standard plumbing soft copper? Or nicop brake line? Did you make the line or buy it pre made for this application?
I had my dad's friend (he's a mechanic) make me the fuel line since i wanted a cleaner look, I think I might bring it back to him to see if he can redo the flare. I started thinking its probably that because it came a a full strait peice and then was cut down and bent to shap so the side that doesn't leak is the factory flare while the one he made leaks. Hopefully its able to be re-flared
The flare on the end of that piece doesn't look proper to me.
Go ahead and have it properly redone. That should solve the problem.
Im not an export on flaring lines or anything, but when i was doing the break lines on a Miata I once had, i kept getting issued with leaking. Came down to the fact that i was using a single flare, when i should've been using a double flare. I believe that's what its called, whenever your effectively squish the flare to make it more rounded.
No idea about 50s Cadillac's though, quite possibly that's only a Japanese thing or a 90s and so forth thing.
-Morgan
Maybe it is the picture angle but the flare on the line and on the elbow look like a different degree. Or maybe the flare on the line is not deep enough although it does look like a double flare.
Harry
When all else has been checked be sure the flare is SAE and NOT AN
Greg Surfas
Maybe the guy has one of the big deluxe flaring tool sets and got one of the dies flipped around in the tool? Many of the nice hydraulic tools have a lot of options for things like DIN, 37, and 45 degree and often times which one you get depends on which direction you insert the die into the tool.
Quote from: TJ Hopland on May 19, 2025, 10:03:48 AMMaybe the guy has one of the big deluxe flaring tool sets and got one of the dies flipped around in the tool? Many of the nice hydraulic tools have a lot of options for things like DIN, 37, and 45 degree and often times which one you get depends on which direction you insert the die into the tool.
Oh ok im assuming my mechanic should know the correct type of flare to fo now but what kind should I be telling him? Double flare?
Looks to me like the cheap flare tool was used to create the flare, you can tell by the lines cut into the pipe just behind the flare.
It also looks like the flare is not centered, more meat up top but thinner on the bottom.
Nothing you can do but have it redone. It should be a double flare. Also when you go to install it next time, don't try to tighten it as much as you can, some of these you can overtighten and cause a leak. You kind of have to just tighten them little by little while checking for leaks.
In spite of the poor angle of the photo of the flare and no side view of the flare it is really hard to tell, at least for me with any certainty that the flare is bad. But.... it looks that way. The marks from the flaring tool have nothing to do with the integrity of the flare.
Maybe for a test reef on the nut and get it gorilla tight. If you crack the fitting you're only out a couple of bucks. If it stops the leak, you have an answer. That is not a repair. You are still going to have to replace the line.
I can't see if the outlet side is connected. If it is I am curious about is the angle off the pump not being a true ninety with the long run. If so it looks like the line was made an eighth of an inch or so long and the line was horsed into position.
Additionally are you going to support that big filter? Regardless of how smoothly the engine runs there are vibrations and copper work hardens with vibration leading to cracks. Copper lines are bracketed for support to prevent that from happening. Is it a guaranteed result in your application, I dunno, but worth considering.
If I were doing that job on my LaSalle and I had made the line, installed it and it leaked plus I had to bend the ninety to get it to line up, I'd have simply saved the fittings, measured a little more carefully and made a new one.
I'm not ashamed to admit I had to scrap more than one line in my wrench turning days for making a poor flare or not measuring precisely.
tony
My point about the marks from the flare tool on the pipe was only to say it appears the tool was one of those cheaper ones you can get from pretty much anywhere. The pneumatic tool's clamp are longer, leaving more indents. Problem with the cheaper flare tool is that it's sometimes difficult to get a perfect flare out of it, sometimes the die doesn't fit perfectly center in the pipe you're working with and the flare comes out lopsided. Then when you do get a good first flare and think you've got it beat, sometimes the die shifts to one side when you're clamping down on it to get the double flare! I've had to redo flares many times with that tool but who really wants to spend hundreds on a pneumatic when you've only got a few to do here or there?
Just like a lot of things, flaring copper tubing takes a lot of practice and mistakes before you get it right MOST of the time. It is also a skill that can degrade through lack of use. When I encounter a leaking connection (that I did) and I know it's tight enough I don't wast time but just reflate it
Greg Surfas
I agree a collet, pneumatic or hydraulic works well in a shop environment. In the field, not so much, especially if the end is close to a bend. Each have their place. I have fifty plus year old Blue Point double flaring tool that does a fine job. The ones available today, Eastwood and the KD double flaring tools work well.
The tool needs teeth to hold the tubing. It has to be tight to keep the tube from moving down in the clamping tool. I's really not a big problem with copper tubing but with hard line brake and fuel lines the clamp has to be very tight. That is one of the problems with some of the modern inexpensive flaring tools, many of which aren't hardened sufficiently or the tooth profile is poor not allowing the tool to get a good bite on the tube.
THe keys to getting a good flare are the outside chamfer on the tube,a perfectly square cut, deburring the ID and OD then and getting the protrusion of the tube correct. Chamfering the OD is a little trickie to do off hand on a bench grinder and takes practice to do well. It's the key to a good double flare. Same for getting the correct protrusion and using a little lube. I have a milling cutter that puts a nice chamfer on the tube and makes me look like I know how to make a decent double flare that won't leak
tony
I still use the flaring tools I got when I was 12 years old, 71 years ago and my flares are as good as the patience I put into them
About the same for me. I have my dads' Blue Point from around '58 when I was 14 and have had it ever since. It went missing around '68 so I bought another Blue Point from the Snap-On man. THe original showed up packing for my move to California in '79 so now I have two.
tc
With the basic parallel bar sets setting the tube height and needing the bars to be tight were key elements that took me a while to figure out. The height is set by laying the proper die on the bars and aligning the end of the tube with the first step on the die. That is why that step is there.
The trick to clamping tight is to first crank down on the nut nearest to the tube then crank down on the far side. You do it this direction because the far one has the leverage. If you don't get it good and tight the tube can slip and you won't get a good flare. Knowing those tips even the cheap tools can do a decent flare on the small steel tubes. That was all I had and used for many years.
My best flares are always on the tube with the nut sitting on the table next to me....
How true.
Years ago when I had some time to screw around, I took a 3/8 tube, flared both ends and cut it into two unequal lengths. I drove a shaft into each piece, leaving one side long. I bored and threaded one end and cut a corresponding thread on the pice with a protruding shaft. IIRC, a #3-48 thread. I cut a relief in the long threaded end so when the pieces were screwed together the joint was virtually invisible. To make sure, my final op was to make a couple thousands skim cut along the length of completed tube.
When I had a victim, I'd say "Damn! I forgot, I have to fix a fuel line I left the nut off of. Hold my beer." I'd grab the tube and nut hold both behind my back or turn around and unthread the tube and put the nut on, sometimes backwards and hand it to him and wait for a reaction.
tony