If all the R12 hasn't already leaked out into the ozone layer, then yes, you do.
I had a shop suck it out for $20 a a gew years ago.
It seems like he should have paid me since he gets my R12 which is like gold these days, I'm told.
On an 89 Jetta I just did, I did the conversion without first removing the R12 becasue it had all leaked out.
I could tell because when I pushed the valve in nothing came out.

Thomas Brobst
Accu-Sort Systems, Inc
Staff Mechanical Engineer
215-721-5061
fax 215-799-1600

If we knew what it was we were doing, it would not be called research, would it? -Albert Einstein 

>>> "Ronald Hay" <hayr@earthlink.net> 7/1/03 >>>
Do you have to vacuum the system out before you put 134 in there? I have
3 cars that need this done. Thanks Ron

> [Original Message]
> From: Thomas Brobst <TJBROBS@ACCUSORT.COM>
> To: <vanagon@GERRY.VANAGON.COM>
> Date: 7/1/03 7:17:48 AM
> Subject: Re: Used Van Help: I bought the Van!
>
> FWIW I converted my '91 to use R134 instead of R12
> It's a lot cheaper than $150 and you can do it yourself.
> The conversion kit (from InterDynamics) was about $35 at Advance Auto
Parts.
> I'm sure most parts stores carry this.
> And,  if you subsequently find that there is more wrong than just needing
a charge...you're out less money.
>
> Thomas Brobst
> Accu-Sort Systems, Inc
> Staff Mechanical Engineer
> 215-721-5061
> fax 215-799-1600
>
> If we knew what it was we were doing, it would not be called research,
would it? -Albert Einstein 
>
>
>
> >>> TJ Hannink <tjhannink@YAHOO.COM> 7/1/03 >>>
> --- "rmstewart@mac.com" <rmstewart@MAC.COM> wrote:
> > I am having it shipped up from Florida by auto
> > shipper. The van had been
> > with one family for it*s entire life span.
>
> > and the AC Needs recharging another $(150 incl.
> > labor)
>
> In Florida, when the used car ad says 'A/C needs
> recharging' it really means 'A/C need recharging after
> replacing a couple of major components that we didn't
> want to spend the money on'.
>
> Here, used car owners tend to unload older vehicles
> when the A/C fails and major ($$$) repairs are needed
> to get it operational. Most vehicles are unusable in
> here as daily transportation without operational A/C.
> Either the A/C failure was recent, they haven't been
> using the van for the last 4 months, or they just
> drive at night :>).
>
> Good luck,
>
> Good luck,
>
> =====
> TJ Hannink
> Goldibox - 1987 Vanagon Camper, Wolfsburg Edition
> Winter Park, Florida
> http://home.earthlink.net/~tjhannink/
> http://groups.yahoo.com/group/wolfsburg_campers
> http://photos.yahoo.com/tjhannink [Vanagon] Album
>
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