fuel sending unit question

[rattlsnak]

I'm in the process of wiring a fuel sending unit in my fuel cell and had a wiring question. ('72-911) There are three wires, a-black,b-green,c-brown on the original sender plug. Key on, Black is 12v, Green is 2-4v, and Brown is ground. On my sending unit in the fuel cell, it has a terminal for a-12v, b- ground, c- sender, d-warning. I hooked them up using a-black ,b- brown, and c- green. I have about 1/4 tank of gas and the gauge read 3/4.

I havent taken it out yet to move the 'slider' but am I missing something here? Unless its stuck I'm feeling like the sender is bad.
Anyone wire one of these up before? Are they compatible?

[len911]

rattlsnak, I'm in the middle of a complete rewire of my '74... Here's how the fuel sender works... Green wire is connected to gauge, black wire is connected to the warning light and brown is connected to ground.

Fuel moves float up/down changing resistance and making needle in gauge move. Warning light is activated as the float reaches a certain point. It actually closes a contact to ground. Light has power comming from the dashboard, closing switch turns it on.

Check out http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_82SC_Part5-2.jpg

Hope this helps... Lou

BTW, just thought of something... I think you might need to reverse the + and - on your fuel cell sender... Tested the gauges over the weekend and it looks like the fuel gauge is actually reversed from the rest of the other senders...

[rattlsnak]

Ok, cool. its looks like if i move my black wire to the "warning" terminal it may work that way. Im just not sure that this one is wired that way.

[Asjac]

Hate to bring up an old thread but I need the resistance range of the stock sending unit on a 1987 911 Carrera. Anyone know??