Add 2-nipple vapor return fuel sending unit-1971 Satellite?

My newest project, a 1971 satellite 4-door, is leaking fuel like a sieve when the almost-new tank is filled past halfway. Since I need to pull the tank anyway, and since I will want to add a vapor return line, I was hoping to be able to simply buy a 2-nipple sending unit for a newer B-body that would be plug-and-play. Does anyone know if I'll be lucky enough for this to work out?

I'm attaching a photo of a similar sending unit that I found on the 'net; application unknown.

Thanks!

my guess is you may have to tweek the shape of the pickup tube and possibly re-bend the float arm to get close to your original shape[s]. then there is the possibility the swing of the float arm will not be the correct distance as the original. in other words, it may stay full for quite a while, then drop to empty rather fast, or drop to 3/4 from full somewhat quick, then be relatively accurate for the rest of the tank. i'm pretty sure the diameter of the sending unit is the same, so the gasket and retaining ring will work. you may or may not have to file a new orientation notch. if you don't mind experimenting a little, i would try it. but i like to try things just to see what happens or what will fit especially if someone says it won't work.

Is it leaking past the seal?

It is leaking at the doughnut gasket between the sending unit and the tank. Whoever replaced the tank didn't get it to seal, and never went back to fix it.

Here is a 3/8" we have for that car.

http://www.dixierestorationparts.com/product.cfm?pi=3FF69E03-D53D-4E7B-57C2DCB813708B4A

Jimmy G the JB weldmaster! Please tell me you no longer have my fabbed metering rod caps up on your wall of shame AKA as your garage door. Sending units that read correct are a rarity (mainly replacement ones) so if yours is OK there I would drill a hole in the circular flat & solder in a nipple. As said if going with another sender you'd want its dimentions (line shape/float arm configuration) the same as your good one in there now & have the lower horizontle bend of the line just off the floor as there is always some water etc that is heavier than gasoline & you dont want that in your carb (& an occaisional tank siphoning to clean it out). Why are you dropping the tank? there's been issues with replacement sending unit lock rings & I'd get an original one & good visual for bent tangs & likely that'll take care of it (the leak) plus a good circular gasket under it. Tell ya what, send me back my caps & I'll send ya a good OE lock ring!

Hi Robert:

Apparently, I'll never live that JB Weld thing down! By the way, the JB Welded distributor slots are still in there, and still just fine, thank you very much!

Regarding the Satellite tank, I took a quick look-see, and I'll at least have to let the passenger side of the tank droop quite a bit to get the sending unit out of the tank. that might be the plan.

I'll PM you later and we'll catch up.

ETA - I tried to PM you and you are over your limit of PMs. Clean out your mailbox, man!

I think your plan will work fine. Need to get the correct sending unit for the car with return nipple. Agree the gauge will likely be a bit funky with the re-pop sender.

You probably already know this, but leaks at the sender are often caused by thinner material in the re-pop lock ring and gasket. There is just not enough clamp. Cleaning up an old lock ring if you have one would help. I don't know the source for a thicker gasket... maybe you will get some suggestions or try a couple sources. You can stack 2 thin ones to get it to seal if all else fails.