Even with a new sensor and o-ring I had a leak too.
I used some plumbers tape around the threads.  So far so good.

>>> John Rodgers <j_rodgers@CHARTER.NET> 6/30/2003 1:31:24 PM >>>
In every instance I've expereiced the coolant around the coolant level
sensor, the sensor itself had a crack in it. Give it a careful
inspection using a magnifying glass. Your problem may be a crack, not
an
"O"- ring.

John Rodgers
88 GL Driver

Lee Kouns wrote:

>I'm getting coolant leakage around the coolant level sensor in my
'87.
>I'm guessing that I need to replace the seal (o-ring?) for the
sensor.
>Any suggestions on the best tool to use would be appreciated. I
assume
>that removal of the whole tank is not necessary.
>Thanks in advance,
>Lee Kouns
>
>
>