Have you confirmed whether the compressor clutch is still engaged?  On
Mercedes AC systems there's a KLIMA relay which controls the compressor
clutch, among other things.

On Fri, Jul 1, 2011 at 8:15 PM, John Rodgers <inua@charter.net> wrote:

>  My buddy here has a 1990 325i BMW with an A/C problem. When the system
> is charged and turned on, it runs for 4 or 5 minutes and can be felt
> blowing cold air. Then there is a loud click-click up under the dash and
> the air stops being cooled. I suspect this is the expansion valve acting
> up, but don't know for sure. I have been told that is where the valve is
> located, and if so - it appears to be a beast to get at - like the
> heater motor on the Vanagon - the dash has to come out.
>
> Can anyone confirm this? or tell me what they think of the situation and
> what steps he might take to remedy the problem?
>
> Thanks,
>
> John
>
> --
> John Rodgers
> Clayartist and Moldmaker
> 88'GL VW Bus Driver
> Chelsea, AL
> Http://www.moldhaus.com
>

--
Casey