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Old 12-26-2019, 04:21 PM   #1
forestb
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Fuel line

What size of fuel line should I be using on my slightly modified carbureted 350 with an mechanical fuel pump and an under bed gas tank? I am planning on using aluminum fuel line
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Old 12-26-2019, 05:37 PM   #2
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Re: Fuel line

3/8" is what I use...what size is your pickup tube?
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Old 12-26-2019, 07:48 PM   #3
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Re: Fuel line

I’m not sure. It is a Jazz fuel cell. The fitting that comes out of the tube is an AN8 fitting so I am assuming that the pickup tube on the inside is also AN8
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Old 12-26-2019, 09:20 PM   #4
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Re: Fuel line

in the -an size ive only used the -6an..which is about 3/8"
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Old 12-27-2019, 04:02 PM   #5
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Re: Fuel line

6AN = 3/8"
My opinion is go with 3/8". I thought long and hard about a 5/16" line but there isn't much support for that in fittings etc. Besides in the future if you ever want to upgrade your set.
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Old 12-28-2019, 07:49 PM   #6
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Re: Fuel line

Sounds like the 3/8 is the way to go. Can I use hard line all the way from the tank to the fuel pump? Or do I need to have a soft line hooked up to the pump to absorb the vibration of the motor?
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Old 12-28-2019, 07:54 PM   #7
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Re: Fuel line

You dont have to use rubber...but I would just because...
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Old 12-28-2019, 09:43 PM   #8
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Re: Fuel line

Yes use a short rubber piece.
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Old 01-06-2020, 02:53 PM   #9
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Re: Fuel line

You should have rubber (or some sort of flexible hose) that connects the hard fuel line on the frame to the fuel pump, and also from the tank to the hard fuel line attached to the frame too.

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Old 01-21-2020, 05:11 PM   #10
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Re: Fuel line

If I use a 3/8 in stainless line what is the best way to connect a rubber fuel line to it?
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Old 01-21-2020, 05:45 PM   #11
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Re: Fuel line

You could put a bubble flare at the end and get a stainless crimp clamp for the hose when you slide the hose on, It would look better.
Or you could get an 6AN push lock to 3/8" tube crimp fitting.
There are numerous ways. You could get wild and do compression to 6AN:


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Old 01-23-2020, 05:55 PM   #12
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Re: Fuel line

You could replace your fuel pump with one that has NPT fitting and then you could run -6 all the way from the tank to the fuel pump. And then -6 up to the carb.
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Old 01-23-2020, 06:08 PM   #13
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Re: Fuel line

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Originally Posted by LS short box View Post
You could replace your fuel pump with one that has NPT fitting and then you could run -6 all the way from the tank to the fuel pump. And then -6 up to the carb.
That's what I have. I don't know if I want to spend that much money. I also would need to get line that will stand up against California Gas.
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Old 01-27-2020, 07:28 PM   #14
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Re: Fuel line

I realized today that my holley fuel pump is leaking from one of its gaskets. What fuel pressure pump do you all recommend for a under the bed fuel tank?
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Old 01-27-2020, 08:41 PM   #15
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Re: Fuel line

Thought you had a mechanical pump?
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Old 01-27-2020, 09:14 PM   #16
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Re: Fuel line

It is
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Old 01-27-2020, 09:22 PM   #17
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Re: Fuel line

I’m sorry I think I was looking at the free flow rate instead of the fuel pressure. Some of the pumps have different free flow rates so I was a little confused.
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Old 01-27-2020, 09:35 PM   #18
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Re: Fuel line

Do I need to drain my oil in order to replace my fuel pump.
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Old 01-28-2020, 08:40 AM   #19
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Re: Fuel line

Quote:
Originally Posted by forestb View Post
Do I need to drain my oil in order to replace my fuel pump.
No not at all.
http://67-72chevytrucks.com/vboard/s...&postcount=492

Last edited by The Rocknrod; 01-28-2020 at 08:47 AM.
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Old 01-28-2020, 06:00 PM   #20
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Re: Fuel line

Don't have to drain the oil. But as you pull the old pump out slip a small screw driver under the push rod to hold it up. Also its easier to install the new pump with the push rod all the way up so have someone bump the engine to rotate the cam.
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