REDUCER FOR FUEL LINE TO CARB

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soonercruiser

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The old guy and his son who put a 318 in my 67 Barracuda, have a fuel line coming off the carburator of what looks like a 8 inch long rod.
The problem is the adapter on the end is probably 1/2 inch diameter, and they have run this one 1/2 inch rubber hose to the 5/16 inch nipple off of the fuel filter.
They used 2 hose clamps near each other to close down the 1/2 inch line enough on to the 5/8 inch fuel filter nipple.

I notice thai as I was replacing the fuel filter,. and had a devil of a time tightening the hose clamps down enough to not get a fuel leak.
It looks to me like what is needed is a reducer hose from 1/2 to 5/16.
I can't seem to find a rubber one that size; but found a Silicone reducer.
My question is ......Is Silicone OK for the fuel line?? Most of what I see on the WEb says "No".

And I admit that I hadn't removed the 1/2 inch hose off of the carb rod yet.
It was pretty resistant to removal, even with the clamp loose, and I didn't want to dig a bigger hole for myself.
It could be that they clamped the rubber hose over what could be a fiting at the end of that rod, just being lazy. Wouldn't suprise me from the other stuff I have discovered.
And, I just might need a fitting with a hose adapter on the end.
 
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A picture would be more help.

Don't use silicone............Get rid of the cobbled crap and replace the line. Should be a steel 5/16 line to the carb connected to the 5/16 fuel filter nipple with short pieces of neoprene hose in and out of the fuel filter.
 
No reason for 1/2 line anywhere in a street car.
Even our 10 second Race cars are happy with a 3/8
line.
 
there's fuel line reducers out there: plastic, brass, threaded, etx. so it's just figuring out what you've got and what you need.

for example here's a brass one: HOSE BARB BRASS UNION 3/8" X 5/16" (HB-BRUN-00C-00A)


but, depending on what you've got cooking it may be in your best interest and safety to just replace everything. that way you don't wind up with a cobbled together mess and potential for break down or spraying fuel all over a hot engine bay.

now let's see them pics!

edit: you say 1/2" thick, so i'm guessing that you're measuring the outside of the fuel line. it's likely that your lines are 5/16 or 3/8" ID
 
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there's fuel line reducers out there: plastic, brass, threaded, etx. so it's just figuring out what you've got and what you need.

for example here's some barbed brass ones: LTWFITTING 1/4 in. x 3/8 in. I.D. Brass Hose Barb Reducer Splicer Fittings (10-Pack) HF3913R060410 - The Home Depot

but, depending on what you've got cooking it may be in your best interest and safety to just replace everything. that way you don't wind up with a cobbled together mess and potential for break down or spraying fuel all over a hot engine bay.

now let's see them pics!
Yues, I did see the brass reducers.
But, in the case of brass fittings, they fit inside the hose, so you are further reducing flow of fuel.
I do believe that whatever is under the 1/2 inch hose at the end of the card tube will be the determining factor in what I have to do.
 
Yues, I did see the brass reducers.
But, in the case of brass fittings, they fit inside the hose, so you are further reducing flow of fuel.
I do believe that whatever is under the 1/2 inch hose at the end of the card tube will be the determining factor in what I have to do.
unless you have something that's pretty nasty, 5/16 is all you're gonna need on the street and 3/8 is what most track cars use. so, i wouldn't really be worried about flow, especially on a 318.
 
Only you can prevent an under-hood fire. Replace that rube goldberg.
 
What carburetor do you have? If you have actual 1/2" hard line going into the carb, it sounds like you're missing the correct carb inlet fuel fitting. Go to the Edelbrock or Holley (or supplier of your choice) website and look up the correct inlet fitting for your model carburetor, and then put it together correctly. The sooner the better.
 
As stated, pictures would be helpful. Someone here may have just the parts and pieces to correct the problem.
 
Thanks for the pointers and tips.
I got a technician at Summit Racing to help me correct the fuel line fitting problem.
Ordered an new Banjo line with an AN connection to their fuel filter, which will also have a 5/16 barb on the other end.
This will fit directly to my fuel line via only one 5/16 hose.
That eliminates the second hose length, which was forcing my fuel line forward against the alternator mounting bracket.
This was not a place to cut corners and "make do" with what they had in their shop! :rolleyes:

Here's a picture of what they did.
Their Jerry-rigging is on the left; my work on the right/forward of the filter.
You can see where the extra rubber hose length forces the fuel line forward against the alternator bracket on the bottom right of the photo.
And 2 screw clamps to squeeze the 3/8 inch line down the 5/16 filter nipple.
:eek:

bad fuel line arrangement.jpg
 
DONE TODAY!

Using the Edlebrock filter with 5/16 adapter fitting.
Only one hose needed for Edlebrock Banjo from Summit; and now fuel line is back away from the alternator bracket.

banjo fittings 1.jpg



banjo fittings 2.jpg


Yes! I will do a little fuel line bending for a straighter visual.
But, the most important thing is NO LEAKS - all their Edlecrock connections are great!
* The old man and his son actually had a little teflon tape at the banjo fitting BION!!!! :rolleyes:
 
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