You should not mix refrigerants. That's not just a recommendation,
its EPA rules.

Freeze-12 is (I believe) a mix of R134a and other refrigerants, but
even so, you should never mix refrigerants on your own. Either get
your system recharged with R12, or get your system converted. If you
aren't going to stay with R12, you should get your system properly
converted to R134 (change of oil, receiver/dryer and new quick
disconnect fittings).

On May 30, 2006, at 2:39 PM, Susan Powell wrote:

Got a '87 with a "sorta" working ac.  I got some Freeze -12 but
wondering if it will mix with whatever old R12 is in the system or
should I evacuate the system and start from scratch?  I would like to
just get something in it to help with cooling car but I don't want to
wreck anything.  I have learned alot about vanagons from this forum.
Thanks for the comments.  R, Steve