Fuel Line

[Cape Codder]

Apparently I need some education about the Fuel Lines. I recently changed carburetors. I installed the old fuel line and it leaked at the fitting. I bought TWO NEW lines of which the first LEAKED. The second one is installed and NOT leaking BUT both fittings are bottomed out. When I installed these lines I had the ferrel about 1/8" from the end and even used some thread tape to hold it in place. WHAT am I doing WRONG? Please educate me!!

[Cool Hand Lurker]

First, get rid of the thread tape. It tends to shred and get into small orifices in the carb.

The seal is made by compression of the ferrel onto the line and by pressure forcing the ferrel into the seat from tightening the cap nut. Pull off the line and look to see if there is only 1/8" sticking out of the ferrel. Clean it off. Check the marks on the ferrel to see if it makes contact with the seat all the way around. Then it is just a matter of tightening the nut until it stops leaking.

IF there is damage of any sort to the seat where the ferrel makes contact it will leak there and the seat has to be replaced.

[redmodelt]

I take a round small ball stone and just clean up the seat in the carb just a bit to give the new ferrel a place to seat.

[Keith True]

Take a good look at your new line to determine what kind you have.A lot of the new ones have a ferrule made onto the new fitting,and when you tighten the fitting it breaks loose and kind of locks itself where it belongs on the line.If you try to add a ferrule on that type,it will bottom out before it is tight.Where you are using a different carb and have had two lines leaking,it could very be the seat where the ferrule seats.You can dress the seat with a 7/16 round stone ball.

[Mike V. Florida]

Originally Posted by redmodelt

I take a round small ball stone and just clean up the seat in the carb just a bit to give the new ferrel a place to seat.

http://modela.org/dremel_911.html

[BILL WILLIAMSON]

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You have to tighten the nut until the ferrule "squeezes" in on the line, like a wedding ring on a FAT Mans' finger. Tighten the nut until it feels "tight" & then some more, until you feel it "give" some more. A little grease or Vaseline on the nut & ferrule, will help overcome friction, when "setting in" the ferrule. Hope I SUSPLAINED it well???
A TUBING wrench is BEST, to squeeze & tighten the fitting.
Bill Tight

[Chuck Sea/Tac]

Some ferrules are better than others, and vice versa. As mentioned, look at the fittings and see if they are actually thightening up correctly. I just found a 1/2" compression nut on a natural gas griddle thermostat that was never compressed. Been there several years, why it didn't leak, I don't know. Maybe because it was the end on the burner orfice, so there wasn't really any pressure.

[Cape Codder]

Here is an update to my fuel leaking problem. Well, I first trashed the thread tape as suggested above. I then found the line attached at the filter bowl leaking so after several tightening's I replaced the line with a new one with new ferrels. Well it leaked so I inspected the filter bowl and found where the ferrel goes was not cast correctly. So I removed this filter bowl and installed a new one. If you haven't been counting I'm now into my third filter bowl on the car. After installing the third filter bowl and new line I was able to get it to a very little leak. Has anyone had this much trouble to hook up a simple line to a filter bowl and carburetor. Getting pretty pricey with two new filter bowl assemblies and NO good results.

As before any suggestions would sure be appreciated because I only have less then a month before I leave for Gettysburg. At that time I want it to be PERFECT!!!!

Forgot to say that the fuel is leaking between the fitting and the line not around the fitting!

[Tom Wesenberg]

I had to tin the ferrule on a 1930 Coupe about 20 years ago to make it stop dripping.

Just use enough heat to get a nice even layer of solder.

[barkleydave]

Are you using the correct steel fuel line not copper? Copper will eventually crack from vibration and leak.

If you overtighten a copper line it will deform and leak.

My truck had a copper line from fuel bowl to carb and yup it leaked. I messed with it and finally put the correct steel line on and no more problems. Got my line and ferrules from Snyders.

[Barry B./ Ma.]

On the 31 town sedan I had the fuel line leaked, it was all wet on the outside of the tube. The steel tubing was actually laminated steel and was seeping, probably original,I replaced with a new repro tube and no leaks after.

[Cape Codder]

Thanks to all for the suggestions.
Tom - I haven't tried tinning the ferrule but am considering it because I'm out of ideas.
Barleydave - I have used TWO NEW Steel lines as I said in previous post with NEW ferrules from a local Model A parts guy.
Barry B./Ma - Like I said above I used NEW repro stuff to no avail.
Maybe I'll have to buy another A that doesn't leak. HA! HA! That sure would go over big here.!