Replacing a fuel sending unit on a 1968-1982
C3 fuel sending unit replacement
BY: Chris G (Vettefinders)
Replacing the fuel sending unit on a 1968-
will take approximately
1-2 hours. Be sure to wear safety goggles and disconnect
during this process. You do not need to drain the fuel
tank, but remember that you will be working around gasoline
fumes. The first step is to remove the gas filler door. Open
the filler door and you will see the four screws that hold the
assembly in place. Unscrew these and remove the filler door by
pulling it toward the rear of the car and up.
Next, remove the rubber gas filler
Remove the gas gauge
There are two wires for this on the right side of the
filler. You will
most likely be able to see the three lines that run to
the tank, after
you have removed the rubber filler neck. The two gas
located on the
right side, and the evaporator line is located on the
left. Be careful not to rip or crack these rubber lines,
because it is very hard to put new ones on with such a small
Now use a 1/4" ratchet and a 1/2"
socket to remove all of the bolts around the fill port. Once
they are loose, you can pull the sending unit up a little and
rotate it around so you can pull it out past the hole in the
fiberglass. It will take a good amount of twisting it back and
forth to get the right angle. Also, be careful not to drop
anything in the gas tank, including rust or the old gasket. The
old gasket is most likely a rubber one. You should evaluate
whether you can reuse it or not. Mine was in too poor of shape
You can see where the fuel was sloshing
when the tank was full and coming under the gasket.
Clean the area where the new gasket will
go. I cut a new gasket using the old one as a template.
The new sending unit.
Apply a thin layer of gasoline resistant
gasket sealer on both sides of the gasket, and install the new
sending unit. Put the fuel lines back on, the sending unit
wires, the rubber filler neck, and the fuel door.
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