Jeff, there are some fittings to be changed, but those are not inside, rather they are the fittings used for filling.  A proper evacuation will include purging the old oil, and changing the lubricating oil to one manufactured to be compatible with R134.  I would want a leak down test done.  It is likely that there are leaks, given the age of the system.  And when not used, seals dry out and so on.  mcneely

---- Jim Ogul <jimogul70@GMAIL.COM> wrote:
> My AC doesnt put out cold air on my 85 Westy.  It was that way when I
> bought it.  It has R12 in it.  A local shop tells me that what they do is
> evacuate the system and put in R134 and if the system is ok it will work.
>  I had always heard you have to get into the system and modify it for R134.
>  This local shop has a lot of experience and if its that simple I'd rather
> go that way.
>
> Jim
> 85 Westy

--
David McNeely