Why 4 lines to the fuel tank?

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Why 4 lines to the fuel tank?

Postby djss » Fri Jul 27, 2018 4:55 pm

I have the gas tank off my 1971 Vega, I am going to put it back and but its been awhile and I can't remember where they all go. Why 4?

Does anyone have a diagram?

Thanks
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Re: Why 4 lines to the fuel tank?

Postby cjbiagi » Fri Jul 27, 2018 10:31 pm

I don't know why there would be 4 lines on a 1971 Vega. Some later model cars use more for emissions and a fuel return line etc. My 75 Monza only has 2 lines, I wonder if someone swapper a later model fuel sender on your car?
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Re: Why 4 lines to the fuel tank?

Postby djss » Mon Jul 30, 2018 8:15 am

3 of them of 5/16 and 1 is 3/8, I at least I'm sure about one of them.
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Re: Why 4 lines to the fuel tank?

Postby djss » Mon Jul 30, 2018 11:50 am

I do not think anything has been changed. Everything looked original. This car had a v8 swap back in the late 70's and has been used very little since and kept in a garage. It still had the original fuel pump/sending unit in the tank and it also has a mechanical pump on the engine. It is a wagon.
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Re: Why 4 lines to the fuel tank?

Postby iowagold » Thu Aug 02, 2018 7:36 am

the 3/8 should be from the in tank pump.

the others are evap from the engine and the to and return from the canister and tank vent.

you can verify the 3/8 as fuel feed by pulling the sender.

the other 3 are just vapor.
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Re: Why 4 lines to the fuel tank?

Postby cosvega76 » Thu Aug 02, 2018 8:40 am

Here's the diagram from the service manual. It seems all three vent lines go to the fuel separator, if you still have it.

Fuel tank.JPG
Fuel tank.JPG (133.98 KiB) Viewed 186 times




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Re: Why 4 lines to the fuel tank?

Postby djss » Thu Aug 02, 2018 5:08 pm

I took the trim panel off a couple days ago before I got the diagram and found the metal canister that all 3 of the vent lines go into. I have never seen such a thing. I'm not sure of the purpose of the fuel separator, but I put it back like it was.

It's up and running.
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