Proper fuel line install

[Michael R.]

I am putting a new chrome fuel line in a newly restored Holley 3367 on a 1966 L79. I am looking for suggestions on whether or not to allow the threaded nut to seat the line or to seat the line and then bolt the line tight. Should the carb be bolted down on the manifold or fit the line, then bolt it the carb down tight? I have done it both ways, but I would rather not take any chances of messing up the line or the threads on the carburetor.

[Owen L.]

Re: Proper fuel line install

With a new line on my Rochester, I found it much easier and less chance of cross-threading and flare misalignment by connecting the line to the carb first. With the nut just loose enough to allow the line to swivel as needed, mount the carb to the manifold. The new line was pre-bent, but not to the degree that ensured a direct alignment into the mounted carb body.

[Michael R.]

Re: Proper fuel line install

Thanks Owen. I have had issues with previous lines leaking, and being scared to proceed further. To reiterate, fit the line snug then tighten the line and then bolt down carb.

[Gary C.]

Re: Proper fuel line install

Use this stuff to seal fuel and brake line threads. Works great for me.

https://www.aircraftspruce.com/catalog/pnpages/09-00306.php?gclid=Cj0KCQjw4v2EBhCtARIsACan3nz8kpcGQfmsR8zMf5RDHsgnQJEKhnGJRysEZc7YAboooUluMIG6dHQaAsHNEALw_wcB

Gary
....

[Michael R.]

Re: Proper fuel line install

Use this stuff to seal fuel and brake line threads. Works great for me.

https://www.aircraftspruce.com/catalog/pnpages/09-00306.php?gclid=Cj0KCQjw4v2EBhCtARIsACan3nz8kpcGQfmsR8zMf5RDHsgnQJEKhnGJRysEZc7YAboooUluMIG6dHQaAsHNEALw_wcB

Gary
....

Thanks Gary, product on its way.

[Leif A.]

Re: Proper fuel line install

Leave the carburetor loose while you fit the fuel line to the fuel inlet on the carb. It makes it much easier to install the line when you can finagle the carb around instead of trying to bend the line a little. Once the fuel line is finger snug, then you can tighten the carb down (finger snug the four nuts on the studs for the carb and then and additional 1/4 turn with a wrench...don't overtighten these nuts as you can bend the base plate). Once the carb is tightened, then using two wrenches (one for the fuel filter nut and a flare nut wrench on the fuel line) go ahead and snug the fuel line. Again, there should be no need to go gorilla on the fitting. Hope this helps.

[Michael R.]

Re: Proper fuel line install

Thanks Leif, I plan on following this to a tee.👍

[Ronald L.]

Re: Proper fuel line install

Same car, looking for a picture of the fitting that goes intot he Holley 3367, can soemone post please?

It seems the repro world doesn't have the 350HP version?

I am putting a new chrome fuel line in a newly restored Holley 3367 on a 1966 L79. I am looking for suggestions on whether or not to allow the threaded nut to seat the line or to seat the line and then bolt the line tight. Should the carb be bolted down on the manifold or fit the line, then bolt it the carb down tight? I have done it both ways, but I would rather not take any chances of messing up the line or the threads on the carburetor.

[Gary B.]

Re: Proper fuel line install

Ron,

Do you mean this fitting (with incorrect (?) black plating) shown in an old DB posting?

Gary

FF145225-F9D0-461F-BE86-967D2086C993.jpg

[Duke W.]

Re: Proper fuel line install

Pipes with flare fittings secured by B-nuts like brake and fuel pipes can sometimes be difficult to seal. With the carb on the manifold and the nuts loosely installed install the pipe, get the B-nuts started on both carb and fuel pump, then run them up finger right, and torque the carb nuts.

Using ONLY a five sided flare fitting wrench tighten the B-nut and then loosen. Do this at least two more times tightening the nut a bit more each time. Start and check for leaks. If any are noted, repeat the above procedure.

Don't put any kind of sealer - teflon tape -whatever on the B-nut. That does nothing. The seal HAS to be between the flare and the fitting. The fitting acts as a die to make the flair conform to the fitting tightly and seal.

I don't recommend SS brake of fuel lines because SS is much less ductile that the typical plated low carbon steel material, which can make sealing SS lines very difficult. Given the way most of these cars are used and pampered, conventional plated mild steel tubing fuel and brake pipes will likely last at least 100 years.

Duke

[Ronald L.]

Re: Proper fuel line install

Gary - that area yes...Was there a chance early 66 cars got the banjo style fitting to the Holley? Ill get a picture Monday.

Duke - spot on - unless you're out there running the Gold Ball Rally, OEM lines will last ...

[Gary B.]

[James G.]

Re: Proper fuel line install

Years ago I had problems with new lines not sealing correctly on the flares.
Here is what I have been doing ever since. --
With everything off the car --
I snug the fitting with my fingers then spin the line 360 degrees around a few times then snug again with my fingers and spin a few more times, I find this "laps" the flare with the fittings and after snugging them with a flare wrench have had no problems with any leaks what so ever. It works with SS or mild steel lines.

[Gary B.]

Re: Proper fuel line install

Use this stuff to seal fuel and brake line threads. Works great for me.

https://www.aircraftspruce.com/catalog/pnpages/09-00306.php?gclid=Cj0KCQjw4v2EBhCtARIsACan3nz8kpcGQfmsR8zMf5RDHsgnQJEKhnGJRysEZc7YAboooUluMIG6dHQaAsHNEALw_wcB

Gary
....

[Leif A.]

Re: Proper fuel line install

I know this is a three-year old thread, but I’m about to connect the chrome line to the carb inlet on my ‘’66 L79. So, I was rereading this thread today. For sake of clarification, the EZ Turn product is a thread lubricant, not a thread sealant. I believe its intended purpose is to lubricate the threaded interface so that more of the applied torque goes into compressing the flared junction that is the sealing interface, and less of the applied torque goes into wasted friction at the threads.

Gary

Gary,
A partial quote from the link posted by Gary Chestnut:

"EZ Turn is a specialty lubricant/sealant used for fuel and oil line..."