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wagone
10-12-2005, 10:00 PM
This might sound like a dumb question--and perhaps it is. But I'm having trouble with flare nut connections leaking fuel at the junction block joints. It is not possible (no matter how desirable) to replace the fuel line in one section (as the original line was) without removing the body from the frame. But in using shorter sections of steel tubing I end up with leaks at the junction block joints. Any thoughts on how to get these lines installed without leaks--for SAFETY? After I get the joints tightened up I'm still left with a certain amount of fishing and bending of the tubing to get it positioned properly and this SEEMS to cause the leaks.
wagone and Avanti I

Dan White
10-12-2005, 10:37 PM
Perhaps this is a another dumb question so please do not be insulted. I assume these are double flare joints not single? If double flare, did you really double flare and not single flare the tubing. This will definitely lead to leaks. Also are the seats in your junction blocks in good shape? If not no matter how tight they will leak. I did away with flared joints on my Hawk and other cars as I replaced the fuel lines. I now use Swagelok or the Parker equivalent tubing fittings, which are used in high pressure gas and liquid lines. They never leak and and are easy to install, but definitely not factory.

Dan White
64 R1 GT
64 R2 GT

whacker
10-13-2005, 12:00 AM
The best solution I have found for this problem is to absolutely minimize the number of joints you have. I assume you are using steel and bending with a bending tool? I've found that it is much easier and safer to use the aluminum racing tubing sold at Jegs, Summit and Speedway in 25 foot lengths. With a little planning you might be able to run the entire length with no joints at all, or maybe just one joint. It is a little tricky to work with,as it comes rolled up and it wants to kink if you try to unroll too much or too fast, but it sure is nice once it is in. It also double flares really nicely. One 25 foot roll will just do one car, with a little left over. When you compare cost of steel, and all the connectors, and the trouble of double flaring in steel, the aluminum is cost effective as well.

Dan White
10-13-2005, 09:02 AM
Whacker I agree with the use of tube bending tools and minimizing the number of joints however, aluminum tubing should never be used for a permanent fuel line except for racing or temporary fixes. Yes it is soft and easy to bend and flare but it is subject electrolytic corrosion, ie it will rot if it is in contact with iron and/or steel (clamps, fittings, frame, etc., stainless is OK) for any length of time, especially if there is any water and/or salt present (this speeds the rot, FAST). In addition it is subject to stress cracking so if you have much frame flex or engine rock you could be in trouble in the area where the fuel line flexes. My background is metallurgy and my company makes a lot of components for miliary and commercial aircraft and most of it is aluminum based. No components are ever used bare, always anodized, chemical conversion coated, or nickel and/or cadmium plated.

I take the opposite extreme, everything I do is stainless. It is a bitch to bend and flare but it is a one time deal and once you get used to using it it is not that bad. I buy it in 10 ft. straight sections and where necessary use one union (see above Swagelok or Parker fittings) for long lengths. Never worry about any corrosion or stress cracks.

Dan White
64 R1 GT
64 R2 GT

BRUCESTUDE
10-13-2005, 12:06 PM
WHEN I REPLACED MY LINES, I TOOK OFF THE OLD ONES, LAID THEM ON THE BENCH. THIS WAY I HAD A PATTERN TO GO BY. I USED THE STEEL LINES, AND ENDED UP WITH ONLY 1 EXTRA UNION.
I AGREE WITH THE PREVIOUS POSTS, AND CHECK THE CONDITION OF THE UNIONS, IF THEY ARE OLD, THEY MAY HAVE DAMAGED SEATS.

wagone
10-13-2005, 12:21 PM
Dan: A reply to your initial comment on double flares. I took the advice of Stan Gundry in his book. Hence I have one short length of steel tubing and two long (or longer) lengths of tubing and two junction blocks. These are new pieces and hence are double flares (I assume--dangerous word) and apparently as I installed these pieces in my Avanti (rather a bitch of a job to get between the frame, hog troughs, floor, and dog legs off the frame), and had to bend them as I went, this put a strain on the integrity of the connections. I guess the solution is to buy new components again and try to be more careful as I bend and wind my way along the frame. I really wish there were a better procedure short of removing the body from the frame. Where could I purchase the Swagelok or Parker fittings? Any other helpful suggestions would be greatly appreciated. Thanks a bunch. Oh, when I stated above that these were new pieces I mean they were purchased (the tubing, that is) already flared. But this type joint must be touchy and not able to stand any strain (caused by bending as I went along the frame and to facilitate attaching support clamps--I assume-- there's that word again). Fuel leaks DEFINITELY get my attention. Two young high school girls were recently killed here as they were burned up in their car after it caught fire following an accident. I wish we could do a better job educating our young drivers on the dangers of automobiles--my neighbor's son is 14 and he already has his license; too young in my opinion! The junction blocks (or unions) are new, also.
wagone and Avanti I

Dan White
10-13-2005, 04:10 PM
Swagelok or Parker are available from various distributors Nationwide. However, I buy my Parker fittings from Royal Instruments (www.royalinstruments.com, the DE division (266 Quigley Boulevard, New Castle, DE 19720, 302-328-5900). Ask for Dominic and tell him I told you to contact them for car parts (Dom is an old racer). I use the stainless version mostly, although brass is also available, and cheaper. A word about fuel lines. Studebaker as well as others use(d) 5/16" lines. You can buy 5/16" fittings but they are special order and more expensive than 3/8". I have converted my Hawk and my '79 Jeep pickup to 3/8" from 5/16" and it works fine, but that is your choice if you go this way. Also, I have converted all of my brakelines over to stainless as well and used Parker fittings for the unions there too. Unfortunately you still need the double flare when you connect to the caliper or master cylinder.

The way Swagelok and Parker fittings work is that there is a 2 piece furrule inside the fitting. You slide the tubing (straight no flares) into the fitting and tighten down the nut finger tight. Then take two wrenches and tighten the nut one and a quarter turns. This deforms the tubing and furrules to form a gas (and liquid) type high pressure seal (in effect you are swaging the furrule onto the tubing hence the name Swagelok). You can remove the nut and the tubing from the fitting but the ferrule will now be permenantly attached to the tubing. Works great and have been using them for many years with never a leak or break. Oh buy a few spare sets of furrules in case you screw up and lose one or need to cut the tubing off and try again.

Dan White
64 R1 GT
64 R2 GT

gordr
10-13-2005, 06:14 PM
It kind of mystifies me that you could have so much trouble with standard flare fittings on a fuel line. I've used flare fittings for brake and fuel lines for years, and on the rare occasion I got a leak, it could usually be attributed to a poorly-made flare on my own part.

I've also used the standard jobber-type compression fittings for trannny cooler lines, again with no grief. I'd consider using them for fuel lines, but never brakes.

If you are assembling the lines into the unions, and then trying to snake the whole mess through the nooks and crannies of the frame, maybe that's your problem. Try cutting the lines to lengths such that the unions will fall in accessible places, and couple them up once the lines have been run.

Of course, you should never use Teflon tape on a flare fitting. Aside from that, possibly you got a load of poor-quality lines or fittings, or else are simply not putting enough torque on the flare nuts to properly seal them.

This is one of those things, where, if I had had the actual car to look at, I'm sure I'd recognize the problem right away. Trying do diagnose from a distance means having to ask all the too-obvious questions.

Gord Richmond, within Weasel range of the Alberta Badlands

Transtar60
10-13-2005, 07:37 PM
Waggone what state do you live in where 14 year olds can get a drivers license??

wagone
10-13-2005, 09:06 PM
Transtar60: I'm in Iowa and 14 year olds can get a school permit type license. I've seen kids driving that likely couldn't see over the steering wheel and might have had blocks on the pedals (the latter an exaggeration, but probably not by much). I don't know if these girls were driving on a school permit or not but one was 17 and the other 14--what a terrible way to die!
wagone

garyash
10-13-2005, 09:09 PM
I had a similar problem feeding new brake lines into my M5 when I rebuilt it and had leaks at the junctions. I finally broke down and bought a good set of flare nut wrenches. They have a narrow opening for the tube and the nut is grabbed on 4 sides and 5 corners, as opposed to only 2 sides/corners with a regular open end wrench. In addition, the wrench heads are thicker so that they can apply more torque without rounding off the nuts. Once I grabbed the union with one big wrench and used the flare nut wrenches, I could tighten the fittings enough to stop the leaks.

Gary Ash
Dartmouth, MA
'48 M5
'65 Wagonaire Commander
'63 Wagonaire Standard
www.studegarage.com

wagone
10-13-2005, 09:46 PM
Thanks for all the advice, guys. Note to Gary Ash: I am using the flare nut wrenches. The problem appears to be lack of room (only about one inch) to get the two wrenchs up into the small space to tighten up the flares and I can't always find room to get the flare nut wrenches on the nuts. Also I BELIEVE the problem is that I find I have to do some bending of the tubing to get it aligned where I need it and to get it attached to the support braces and the connection can't stand the stress placed on it. And Dan, MAYBE the GT Hawks have more room to work with--the Avanti doesn't have much. And I find that as I get older jobs that used to be easy just aren't anymore. Example: I used to think nothing of adjusting valve lash on solid lifters with the engine running (be they Studes or SBCs), but I tried it recently on my Avanti and made a real mess of it--went to setting them .027" cold. As we are all aware, getting older is not a lot of fun.
wagone