From digest.v6.n672 Mon May 19 08:57:46 1997
From: mal_at_eauto.com
Date: Sat, 17 May 1997 18:11:28 -0500
Subject: Re: <all>Air Conditioning problems

I would like to elaborate on Brett's comments in Vol 6, No. 670 regarding <rramirez_at_salestar.com>'s posting.

If the model year of your BMW is between 1980 and 1991 (it varies among the chassis, as BMW changed to a Nippondenso compressor on certain chassis during certain model years), you have a rotary vane compressor built for Bosch and Behr. These compressors contain an elastomer called Viton. Viton disintegrates when it comes in contact with HCF134a and HFC134a-compatible lubricants.

If you do a retrofit, you HAVE to change the compressor (and the reciever dryer). The rotary vane unit WILL fail. Your options are a rotary vane remanufactured with neoprene elstomers (these compressors are hard to find), the BMW OEM replacement (this is a Seiko Seiki unit and it is expensive) or a Sanden or Zexel (aka Diesel Kiki; use of either of these last two requires a new mounting bracket, but these are easy to come by).

Hope this helps.

Malcolm Davidow
Dallas, Texas