Gas tank question

[Pierce Gwynne]

I’m new to my 73’ RR and have no idea what these are for on my gas tank. Vent holes? I don’t know. Any knowledge would be great. TIA

 

[Lefty71]

Don't most of them go to this?? You need the emissions map for your car;
https://www.google.com/search?q=197...gILw&biw=1920&bih=1007#spd=632792467396185479

 

[Pierce Gwynne]

Don't most of them go to this?? You need the emissions map for your car;
https://www.google.com/search?q=197...gILw&biw=1920&bih=1007#spd=632792467396185479

 

[Pierce Gwynne]

I’m not sure really. That’s a whole other realm of things I don’t known lol

 

[moparmarks]

For the vapor recovery system. The four lines go to a small vapor tank mounted on the frame crossmember. From there another line goes to the charcoal canister in the engine bay. Then there are a couple more lines that go to the carburetor and breather system from the canister.

 

[Pierce Gwynne]

For the vapor recovery system. The four lines go to a small vapor tank mounted on the frame crossmember. From there another line goes to the charcoal canister in the engine bay. Then there are a couple more lines that go to the carburetor and breather system from the canister.

Thank you. Would have had no clue

 

[Pierce Gwynne]

And on the sending unit what is the third port for. Ones for fuel ones a ground for the gas gauge and third is for?? Return??

 

[Grabbergreendream]

Correct. There is a return line to the sender.
The 4 lines on the front of your tank go to the vapor seperator mounted on the crossmember for your shocks & looks like the one in this pic from my 73'. I just painted it and it is laying in my trunk by pure coincidence...
The line on the back of the seperator heads up to the engine compartment, but if your car is missing that much you got some research to do...

 

[Pierce Gwynne]

Correct. There is a return line to the sender.
The 4 lines on the front of your tank go to the vapor seperator mounted on the crossmember for your shocks & looks like the one in this pic from my 73'. I just painted it and it is laying in my trunk by pure coincidence...
The line on the back of the seperator heads up to the engine compartment, but if your car is missing that much you got some research to do...

View attachment 781283

Awesome thank you for the info. I have to see if the lines are their I’m praying everything’s their

 

[moparedtn]

Do yourself a huge favor and fetch a factory service manual for the car.
Seriously.

 

[moparmarks]

The return line was only on 440 and Hemi cars.

 

[wahya]

And on the sending unit what is the third port for. Ones for fuel ones a ground for the gas gauge and third is for?? Return??

View attachment 781282

I don't see three ports in your pic. Somebody correct me if I'm wrong ( I have a 71), but isn't that lug for the wire that runs back to fuel gauge? Ground on mine goes to tank strap on metal fuel line.

 

[ODZKing]

Here is a pic from the service manual. Go to my website and download the service manual - http://www.retrorarities.com/images/73DodgeServiceManual.zip
It's in the chassis portion - fuel - 14-53
It's the Dodge manual but this should be the same.

 

[Pierce Gwynne]

I don't see three ports in your pic. Somebody correct me if I'm wrong ( I have a 71), but isn't that lug for the wire that runs back to fuel gauge? Ground on mine goes to tank strap on metal fuel line.

There’s a ground and two ports I’m not sure what the other is

 

[wahya]

Found this pic in a thread from last year. Have a wire with end that looks like this? I must not be seeing what you are seeing. Maybe the ground is not visible in your pic. edit, photo from dadsbee post.

 

[72RoadrunnerGTX]

The fuel tank sender would not have a ground terminal, the terminal pictured is the sender signal connection, blue wire pictured connects to it. The factory used a fuel line to sender bridge clip to insure a ground path for the sender. The pictured sending unit is likely a reproduction sender with a 3/8” pick-up tube, also has a ¼” return fitting. As mentioned above the correct application for it is the 440 and Hemi cars. Other motors used a sender with a single 5/16” pick-up, no return fitting. Have yet to see this reproduced. The return line fitting has nothing to do with the tank vent lines or vapor separator. Cap off the return fitting if not running a return line.

 

[idrivemopar]

Here is a properly setup fuel sender for 73 Roadrunner/Satellite. Some of the new ones do come with a ground terminal, but that's not how it gets grounded. Originally there was one connection for the fuel gauge, the blue wire, the ground was achieved by the strap from the fuel pickup tube out on the sending unit to the fuel line on the car and it should be curved not straight connection on the sending unit. There are no other connections.

Regarding the 4 fuel vapor ports, here is the vapor separator and the connections looking from underneath. All the fuel lines used pinch clamps.

In case you want to see a proper charcoal canister here is that also. The metal line coming up is from the vapor separator on the fuel tank, the one that is closest is to the purge port on the carburetor, the far one is connected to the bowl vent on thermoquad carburetor.

 

[Pierce Gwynne]

Here is a properly setup fuel sender for 73 Roadrunner/Satellite. Some of the new ones do come with a ground terminal, but that's not how it gets grounded. Originally there was one connection for the fuel gauge, the blue wire, the ground was achieved by the strap from the fuel pickup tube out on the sending unit to the fuel line on the car and it should be curved not straight connection on the sending unit. There are no other connections.
View attachment 781608

Regarding the 4 fuel vapor ports, here is the vapor separator and the connections looking from underneath. All the fuel lines used pinch clamps.

View attachment 781610

In case you want to see a proper charcoal canister here is that also. The metal line coming up is from the vapor separator on the fuel tank, the one that is closest is to the purge port on the carburetor, the far one is connected to the bowl vent on thermoquad carburetor.
View attachment 781613

Thank you for sharing. I will save these photos for reference

 

[Pierce Gwynne]

Here is a properly setup fuel sender for 73 Roadrunner/Satellite. Some of the new ones do come with a ground terminal, but that's not how it gets grounded. Originally there was one connection for the fuel gauge, the blue wire, the ground was achieved by the strap from the fuel pickup tube out on the sending unit to the fuel line on the car and it should be curved not straight connection on the sending unit. There are no other connections.
View attachment 781608

Regarding the 4 fuel vapor ports, here is the vapor separator and the connections looking from underneath. All the fuel lines used pinch clamps.

View attachment 781610

In case you want to see a proper charcoal canister here is that also. The metal line coming up is from the vapor separator on the fuel tank, the one that is closest is to the purge port on the carburetor, the far one is connected to the bowl vent on thermoquad carburetor.
View attachment 781613

Do you think I will have problems running my sending unit and just cap off the return or should I return it and get the correct one

 

[idrivemopar]

I went through the same thing, couldn't find the correct sending unit until I found this one, unfortunately, I didn't write down where I got it from, and not sure where the receipt is for it so I wish I could tell you who has the correct one. I guess if you want to keep searching for a correct unit, go for it, not sure if there are any other differences on the one you have that will cause any issues using it, except for maybe installing the ground strap, it probably wont fit without the curved port.