I am replacing my old sending unit while I have the tank off...just saw on e-bay that there is a sending unit with 2 lines:

http://cgi.ebay.com/ebaymotors/68-69-70-Malibu-Chevelle-SS-Gas-Fuel-Sending-Unit-2Line_W0QQitemZ200324895573QQcmdZViewItemQQptZMoto rs_Car_Truck_Parts_Accessories?hash=item2ea44b5355

Can someone help me out here - what is the purpose of the 2nd line and how would you go about installing this? Or should I just stick with the stock 1 line version?? Just curious. :confused:

Some cars like the high horse solid lifter big blocks had a single 3/8 fuel line, and some had a return line as well as the fuel line. Just put back whatever you had originally. What motor is in your car?

It's a 396. I'm thinking I should stick with the single line since I don't want to mess with re-plumbing the thing for a new sending unit.

If this is a 68 you're talking about Bryan, they all had a single fuel line.

The second line is for the vent that loops up inside the trunk then comes back down and ends (open tube). This is the way it is on my 67

The second line is for the vent that loops up inside the trunk then comes back down and ends (open tube). This is the way it is on my 67

68's didn't get any extra lines for anything. Only the single fuel line. No vent or return lines going into the sender, and no lines going to the trunk. The tank was vented with a small plastic vent, near the front rt corner of the tank.

If you're replacing the sending unit anyway, why NOT get a two-tube unit? You wouldn't HAVE to use the return; but it'd be there if you ever had vapor lock issues and wanted to upgrade.

Install it, block the return tube with a plugged rubber hose.