Gas tank sending unit

[45acp]

I am replacing the sending unit for my 83 Jimmy and would like to know what the function is for the 4 outlets. One is the fuel line to the fuel pump and one is the overflow return line. They are all different sizes. What are the functions of the other two? I assume that they go back to the vapor canister but is the function only to equalize the fuel tank pressure?

 

[FWP]

That's right. 4 lines, fuel pump supply, fuel pump return, canister (activated carbon)vent, and gas fill tube vent.

 

[45acp]

FWP, Thanks for the help.

 

[TX Mudder]

You guys kept all that emissions stuff on there?
I capped the extra lines and have a fuel out and a vent, that's it.
-- Mike

 

[45acp]

Thanks Mike (see my email)