C2 fuel line leaks

[Kevin Brooks]

Folks,

Having just rebuilt my 3367 version carb on my '66 327 I have come upon persistent leaks at the ends of my fuel line - the one running from the fuel pump to the carb inlet. It appears that the end of the tube is a double flared 45, like the kind found on brake systems in older American cars. Are these fuel lines resealable, or do they need replacing after every removal? I am having a terrible time trying to stop the leaks - no amount of wrench turning seems to work. I have already drained my gas tank in preparation for line work at the fuel pump end.

Any advice appreciated.

Kevin

[William C.]

Re: C2 fuel line leaks

Check the fitting in the carb for seat damage, and also the line seat for the same. If you had a piece of debris get in there before tightening, it will deforn the sealing surfaces and you will not have a seal. The brass side is more succeptable than the steel (line) side. I assume you are not using teflon or other similar materials that will also contribute to a leak. I've reused my connection many times without generating a leak, just inspect carefully.

[Joe L.]

Re: C2 fuel line leaks

Kevin------

The lines definitely do not need to be replaced each time they are removed. The line should be tinned bundy weld (TBW) and it should definitely have 45 degree, double flares. A few possibilities as far as the leaks go:

1) Someone may have previously replaced the line with stainless steel. Stainless is very hard and resists "conformation". So, it can be difficult to seal. I LOVE stainless steel for all sorts of things. However, I don't use it for fuel or brake lines for this reason;

2) A very small crack has developed in the flared area. It might be imperceptible to the naked eye, so inspect the ends with a magnifying glass;

3) Some other minor defect has developed in the flared end which cannot be "overcome" by the "conformability" of the material.

4) Some defect has developed in the SEAT which is in the fitting which threads into the carburetor body.

Actually, I'd try replacing the line first rather than getting into a lot of effort to determine why it's leaking. You can purchase excellent reproductions of the line you need for a rather modest cost.

[Jeff S.]

Re: C2 fuel line leaks

Kevin

I gave up trying to get the chrome OEM-style pipe and fitting to seal on my '66 with 3367. The plating presents so little friction that the pipe's male fitting at the carb would loosen from vibration or thermal cycles, or something every so often. Too much wrenching on that area could cause problems with that rather delicate primary float bowl. I never had a problem on the pump side -- only at the carb.

Finally, I fashioned a replacement out of a length of brake pipe, and it has worked out OK. Takes lots of fussing & trial fitting to get the bends, compound curves, etc. to line up. With no chrome on the flare or fittings & just the standard 'terne' coating on the pipe & dichromate on the male nuts, it has not leaked. Just don't crank up too tight on while you're doing th multiple fit-ups or you'll work harden the double flares.

[John D.]

Re: C2 fuel line leaks

Kevin, Want a cheater method? Try my favorite Loctite #545. Not available in auto stores typically. Just industrial tool supply houses. MSC, Travers, McMaster-Carr. All on the web. Put a little bit on the ferrel end of the line with a q-tip and then tighten the line with line wrenches.(caution: don't get any in the tube itself-just the edge of the ferrel) I like it to cure a little while. Then no leak. I use it a lot on the fuel injections.
Another example: Some insist on using SS brake lines, etc. Some of those lines have SS fittings also. Very prone to leak. Use a touch of Loctit #545 and leak is gone. I could give a 100 examples of how it has saved me. John

[KEVIN BROOKS]

Re: C2 fuel line leaks

Interesting use of Loctite..
Would a semi-drying liquid gasket (SDLG) sealant work as well? I'm not talking about RTV sealant. I have used something like a SDLG for smaller engine applications, like lawnmowers and tillers, tractor governors, etc. So far, they have worked well. My concern here would be durability and longevity.

[KEVIN BROOKS]

Re: C2 fuel line leaks

I did not put on the fuel lines, so I can't say for sure what material they're made of but, my best guess is, the lines are either SS or Chrome plated. They're shiny and harder than hades!
It is possible something has cracked while I was moving the line around to fit into position. Also possible that either mating surface got contaminated with foreign material.

[John D.]

Re: C2 fuel line leaks

Kevin, I can't answer that questio on the SHLG. My friend started me on #545 years ago. He said Caterpillar used it big time. It's a hydraulic sealant. They wouldn't be using it if it wasn't any good. Few people ever read the directions on the bottle. Shake it good before using. Often you will see it on ebay for a steal. Typically it cost around $30.00
There is only so many times you can use ferrels and fittings over. When fittings take a seat that's it. Go and use it over and you have problems with leaks. On the FI's I seldom use a fitting over for that reason. Unless it's a rare fitting. Good luck, John

[Clem Z.]

several companies sell copper flare gaskets

which help the seal because the copper is soft compared to the steel in the line and fitting

[Kevin Brooks]

Re: several companies sell copper flare gaskets

How would I install coppper gaskets? I would have to fabricate my own lines after cutting off one end, correct?

[Clem Z.]

they go between the female flare on the tubing

and the male flare in the carb fittings. i used these all the time on the 3X2 carb fuel lines as this was the best way to seal them without great effort.

[Clem Z.]

flare gasket picture

http://www.parker.com/EAD/displayCatalog.asp?menu_parkerid=46&menu_gid=2&menu_divid=336&catid=10244&catdesc=2GF%20COPPER%20FLARE%20GASKET&subcatid=10208&viewtype=1&sMode=Details

[KEVIN BROOKS]

Re: flare gasket picture

Just looked at the website. Looks interesting..I'm assuming the gaskets you mentioned would be either of the two types, i.e. without any threads, etc? Which type would you recommend: the straight flare or bell-shaped flare?

[Clem Z.]

2GF were the gaskets i used on fuel lines *NM*