fuel line

[mario]

Tank was out when I got the car, I found a fuel line running up the driver size, and then going under the car I found another running up the center of the car(looks like two tubes) ,can someone tell me what is what PLEASE.

1971 mach 1 351 m

 

[Jeff73Mach1]

Up the center is a return line for vapor. It should come out on the firewall pointing towards the passenger side, and in back it goes to a vent on the top of the fuel tank. If you don't get the rubber line on the vent while the tank is out, it is not possible to put it on when the tank is installed to the best of my recollection.

Up the driver side is the fuel line, it comes out by the steering box, has a short rubber line, another steel line that comes out in front of the shock tower and a short rubber line to the fuel pump. Should any of these metal lines be bent, straightening them can cause them to buckle or crack, so be gentle. The metal lines can rust inside and the rubber deteriorates. I would replace all rubber lines and clamps and blow out the steel lines. Cover the open end with a rag when blowing them out and if you get any significant amount of crap consider replacing them. Also, make sure you have a fuel filter to catch anything that might be in the lines or tank before it gets to the carb.

Hope that is helpful.

 

[jbojo]

+1

That rubber hose must be installed prior to installing the tank. Attaching a pic of the top of the tank and the fitting that goes on it.

The 2 lines up the center are the fuel vapor return line and the rear brake line from the proportional valve.

BTW, I used this line as a return from my fuel pressure regulator for the efi system. The pump provides 70psi and the regulator is set at 50psi so excess fuel goes back to the tank via this old vapor line. I did not have to weld on a return nipple to the tank by doing it this way. Just thought I'd throw this out in case someone else does this.

 

[73pony]

Does anyone have a photo of the vapor line connection from the metal line to the rubber at the rear of the car? My line just stops and is not connected to anything. Where does it connect up front?

 

[jbojo]

Does anyone have a photo of the vapor line connection from the metal line to the rubber at the rear of the car? My line just stops and is not connected to anything. Where does it connect up front?

Attached, the rubber tube connects to the steel line at the bell housing tunnel and goes to the vapor canister.

If you click on the pic they should become full screen so you can view better

 

[73pony]

Does anyone have a photo of the vapor line connection from the metal line to the rubber at the rear of the car? My line just stops and is not connected to anything. Where does it connect up front?

Attached, the rubber tube connects to the steel line at the bell housing tunnel and goes to the vapor canister.

If you click on the pic they should become full screen so you can view better

OK Thank so my line is connected correctly in the front. In the rear fo the car the lie just stops and is not connected to anything. There is a rubber hose hanging down from the top of the fuel tank that has a small round red plastic thing connected to it. Any ideas? Almost looks like a check valve.

 

[jbojo]

Does anyone have a photo of the vapor line connection from the metal line to the rubber at the rear of the car? My line just stops and is not connected to anything. Where does it connect up front?

Attached, the rubber tube connects to the steel line at the bell housing tunnel and goes to the vapor canister.

If you click on the pic they should become full screen so you can view better

OK Thank so my line is connected correctly in the front. In the rear fo the car the lie just stops and is not connected to anything. There is a rubber hose hanging down from the top of the fuel tank that has a small round red plastic thing connected to it. Any ideas? Almost looks like a check valve.

Just a plug? Mine was connected with a rubber hose only.

 

[73pony]

Attached, the rubber tube connects to the steel line at the bell housing tunnel and goes to the vapor canister.

If you click on the pic they should become full screen so you can view better

OK Thank so my line is connected correctly in the front. In the rear fo the car the lie just stops and is not connected to anything. There is a rubber hose hanging down from the top of the fuel tank that has a small round red plastic thing connected to it. Any ideas? Almost looks like a check valve.

Just a plug? Mine was connected with a rubber hose only.

I will try to get a pic tonight and post it. It's not a plug.

 

[jbojo]

OK Thank so my line is connected correctly in the front. In the rear fo the car the lie just stops and is not connected to anything. There is a rubber hose hanging down from the top of the fuel tank that has a small round red plastic thing connected to it. Any ideas? Almost looks like a check valve.

Just a plug? Mine was connected with a rubber hose only.

The PO could have used a check valve to prevent stuff from entering the tank and to use it as a vent line so that a non vented gas cap could be used. My car only had the hose but mine is a 73 so it may be different.

 

[Jeff73Mach1]

could be that someone put in a roll over check valve

 

[mario]

Thanks all, that helped a lot


??? If I put a electric fuel pump on can I deleted the return line

 

[73pony]

Here are the pics I took.


Another shot


And another


And another pic


The only marking on it is "Made in USA" if you shine a light into the hole it looks like a really fine screen inside. There is no gas smell at all.

 

[Jeff73Mach1]

looks like a vacuum check valve- no idea of why they put it in.

 

[mustang7173]

mario,

Here is the Ford master Catalog of the fuel and emissions diagram-

Source: Ford Master Parts Catalog CR: May 1975 pp. 37

mustang7173 :bravo:

 

[73pony]

looks like a vacuum check valve- no idea of why they put it in.

Do you think I should connect the return vapor line to it or just leave well enough alone? I don't have any fuel smell at all.

 

[Jeff73Mach1]

On this point I have no opinion. Mine has been unhooked since I bought the car. My motto these days seems to be "If it ain't broke, break it" so I'm not the one to ask for advice :atomic: