Author Topic: Fuel line question  (Read 1146 times)

Offline shadango

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Fuel line question
« on: April 01, 2009 - 05:18:20 AM »
Anyone know off-hand the fitting size/type  for the fuel line connection at the discharge side of the fuel pump on a 76 318?

I believe that in stock form there is a steel fuel line that runs from the pump up to the carb....

I have an edelbrock 4v carb and it has a hose inlet, so i am looking to either get a preformed oem steel line for the fuel pump and the cut/flare the end and use a hose the rest of the way to the carb. ...or, just find a fitting that will allow me to connect a fuel hose to the fuel pump I guess.....

Any thoughts? Thanks guys.




Offline Bullitt-

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Re: Fuel line question
« Reply #1 on: April 01, 2009 - 07:28:55 AM »
1/2"-20  according to NAPA ... I purchased a pre-flared line that fit both the pump & carb., most any parts store will have. The line from the pump comes up between the alternator bracket & timing chain cover, where the fuel filter is located, then bends 90-degrees just above the valve cover. I had used rubber once but the metal line looks better. You will need a tubing bender to make some of the tighter bends. 
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Offline shadango

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Re: Fuel line question
« Reply #2 on: April 01, 2009 - 07:32:20 AM »
Awesome!  That is great info...Thanks!

Have never bent my own tubes before.....any tricks, aside from getting a small bender?

Offline Bullitt-

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Re: Fuel line question
« Reply #3 on: April 01, 2009 - 07:39:41 AM »
Awesome!  That is great info...Thanks!

Have never bent my own tubes before.....any tricks, aside from getting a small bender?

I have a very cheep bender but it came with the spring-like things to slide over the tube to help prevent collapse ... biggest thing is don't get in a hurry.
Wade  73 Rallye 340..'77 Millennium Falcon...13 R/T Classic   Huntsville, AL
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Offline Chryco Psycho

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Re: Fuel line question
« Reply #4 on: April 02, 2009 - 12:40:50 AM »
it would be a 5/16 " flare fitting out of the factory fuel pump , no way it is 1/2 line

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Offline ntstlgl1970

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Re: Fuel line question
« Reply #5 on: April 02, 2009 - 12:53:33 AM »
I would agree that it's 5/16" inverted flare (where the steel tubing connects to the pump). I've seen some where there is a fitting on the pump that has the inverted flare on it. I think it's 1/8" or 1/4" male pipe to 5/16" female inverted flare.
1/2-20 is heater hose size fittings.
70 Cuda, 7.0L Gen-III Hemi, Viper T56 w/9310 gearset, 3.91's, Megasquirt MS3x v3.57, Innovate wideband, Firm Feel upper arms, torsion bars, springs and strut rods, QA1 DA shocks. I did everything on this car except the fancy paint stuff and I drive it...and I can't seem to stop messing with it....

Offline shadango

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Re: Fuel line question
« Reply #6 on: April 02, 2009 - 04:56:52 AM »
Well, I checked it.....I was able to thread in a 1/2"-20 tap....its a female brass fitting on the pump....should be the discharge side....the other side is a 5/16"" barb, for the suction......

Gonna run the line up as was described , and end it somewhere as it runs along the valve cover....then hose it from there to the carb (barb fitting on the carb).

Here is a pic of what I have going here on the pump......sorry its a little blurry...

« Last Edit: April 02, 2009 - 05:22:35 AM by shadango »

Offline Bullitt-

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Re: Fuel line question
« Reply #7 on: April 02, 2009 - 08:20:45 AM »
The barb fitting may be 1/2-20 also....if so you could remove & have metal all the way
Wade  73 Rallye 340..'77 Millennium Falcon...13 R/T Classic   Huntsville, AL
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Offline ntstlgl1970

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Re: Fuel line question
« Reply #8 on: April 02, 2009 - 03:45:54 PM »
I think the thread size on the 5/16 tube nut is 1/2 - 20 I just hadn't heard it referred to that way before. Sorry about that.
If the barb on the carb is removable and whatever the barb screwed into has a tube seat, that could work. Just make sure there is a tube seat in the carb. Otherwise I think you would have a large fuel leak because there would be nothing for the tubing to seat against.
70 Cuda, 7.0L Gen-III Hemi, Viper T56 w/9310 gearset, 3.91's, Megasquirt MS3x v3.57, Innovate wideband, Firm Feel upper arms, torsion bars, springs and strut rods, QA1 DA shocks. I did everything on this car except the fancy paint stuff and I drive it...and I can't seem to stop messing with it....

Offline shadango

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Re: Fuel line question
« Reply #9 on: April 02, 2009 - 06:55:39 PM »
I was planning on going metal line up to a certain point and then hooking up the carb with hose the rest of the way....

I took a trip to the NAPA store and yes, mission control, we have a problem.  LOL

There is no way to adapt a 5/16" line with 1/2-20 fitting on one end to a 3/8 hose-fitting......

Cant run straight line either......the hose nipple fitting that screws into the carb is about 5/8" and a flat bottom thread....no flare.

I am going to see if edelbrock offers the correct fitting I guess.

I am also considering just running hose once I match the pump and inlet size.....a guy at NAPA was saying that in his day they replaced the metal lines with hose and it kept the fuel cooler and prevented vapor lock what with the metal lines right near the motor.....thoughts on that?

I did find that I have a 750 CFM Edelbrock Performer carb.....seems kinda big for a 318, dont it?  I have J heads and a performer intake....

« Last Edit: April 02, 2009 - 07:27:22 PM by shadango »

Offline shadango

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Re: Fuel line question
« Reply #10 on: April 03, 2009 - 05:34:25 AM »
Think I may have found the answer to my question....

Edelbrock actually offers a kit to convert a 5/16" or 3/8" steel line to 3/8" hose for its carbs....

Now that I know I can got that route, at least I know what I am looking for......

« Last Edit: April 03, 2009 - 10:29:03 AM by shadango »

Offline moper

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Re: Fuel line question
« Reply #11 on: April 03, 2009 - 10:10:05 AM »
Find a new parts guy...     You buy the correct flare adaptor fitting for the carb...

http://store.summitracing.com/partdetail.asp?autofilter=1&part=EDL%2D8090&N=700+115&autoview=sku

You will need the stock sized 5/16 line about 8" long with the inverted flare fitting on it to come from the fuel pump. That will screw right in. I cut one flare end off using a cutoff wheel so it doesnt crush the end of the line smaller. Then clea out the debris from the cut with carb cleaner. Then you can run the 3/8 in line filter (I like the steel can versions over the see thru ones). The next part you need is 3/8 steel line about 30" line. Again, one inverted flare fitting end goes to the carb fitting above. bend the line to come down from the carb, clearing the choke stuff, but no closer than 1" to the intake or valve cover. Place the bends to get it to run down behind the alternator bracket and cut that end off clean with the wheel, so the rubber line sections that come with the filter will connect the 3/8 line to the 5/16 line. Lastly, you need 2 good clamps. 4 spring type come with the filter. use two spring type on the filter ends of the rubber, use the two new clamps to seal the rubber sections to the lines. Make sure the rubber line on the 5/16 section is tight.

That's  how the carn should be connected. Rubber line is a connector only, not a material for making lines. Too much rubber will get you tossed from drag strips too because it is dangerous. 

Offline shadango

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Re: Fuel line question
« Reply #12 on: April 03, 2009 - 10:26:15 AM »
So the filter you are using has an end that is 5/16 hose and the other is 3/8"?

Got a part number by chance?

Offline ntstlgl1970

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Re: Fuel line question
« Reply #13 on: April 03, 2009 - 02:49:29 PM »
What I think Moper is saying is that you would run 3/8" steel line from the carb to the (3/8") filter, short sections of 3/8" fuel hose at the filter and using good clamps, clamp the 3/8" hose from the fuel filter inlet down onto the 5/16" steel line from the outlet on the fuel pump.
70 Cuda, 7.0L Gen-III Hemi, Viper T56 w/9310 gearset, 3.91's, Megasquirt MS3x v3.57, Innovate wideband, Firm Feel upper arms, torsion bars, springs and strut rods, QA1 DA shocks. I did everything on this car except the fancy paint stuff and I drive it...and I can't seem to stop messing with it....

Offline shadango

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Re: Fuel line question
« Reply #14 on: April 03, 2009 - 08:11:38 PM »
I stopped at a mom and pop hardware store today and found what I think will work....the guy there guarantees me it will seal good..he suggested some teflon tape or permatex.......LOL

Just have to pick up the 5/16" tubing from napa and a bending tool from harbor freight....