The only thing that ended up working for me is to take the pipe off and
attack it from the inside with a good penetrating oil (J. B. Blaster).
Otherwise you will never be able to get to the threads where the "weld"
occured. Repeated heating with a torch along with repeated rapping with a
hammer. Make sure you have a pipe wrench handy for when you srip the flats
off the nut (WHEN, not if). A three foot or so length of pipe for a
additional leverage on the pipe wrench is also good.
     Be prepared to near destroy the old sensor while trying to take it off.
If it is "welded" on there too tightly is is possible to snap the nut off
and leave the theads in the pipe.

     If I had to do it over again I would pull the exhaust pipe and take it
to a local machine shop. They will get it off for about $15 or so provided
you have not done too much damage to the sensor trying to take it off
yourself.

    If yours is anything like mine pack a BIG lunch and tell the wife you
will be gone for a day or so and to ignore any shreaks of profanity coming
from the garage.

> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]On Behalf
> Of TWessner
> Sent: Saturday, February 06, 1999 11:29 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: O2 Sensor
>
>
> Hi Guys!
>
> I'm in the process of changing my O2 sensor on my 84 Westy.  The
> old sensor
> seems to have become severely corroded and I'm having a heck of a time
> getting it to come loose.  Any suggestions other than massive doses of
> WD-40?  Any tips would be much appreciated.
>
> Thanks,
>
> Trent Wessner
> Saskatchewan, Canada
> twessner@cableregina.com
>