I'm having this done today on my 300D with a bad compressor. It's required for a new compressor warrentty, and I'd not put a new (or repaired) compressor in without one. There is no way to remove the crud from a parallel pass condenser or evaporator, especially the evaporator, and sooner or later grit will get into the compressor, wrecking it.
I'm not sure why there isn't one in there to start with. My mechanic friend always puts on in when replacing a compressor. Leaving it at vacuum and having it drop to 23" means one of two things -- there is some water in the dessicant (most likely) or a tiny, slow leak. Leaving the vaccum pump on overnight if the pump will take it is an excellent idea, or it not, close it and leave it with gauges on as long as you can before charging. This will evaporate more water and low vapor pressure contaminants. Also, you can set the air to recirc and heat to max and bake out the evaporator before you charge, too. Won't get it really hot, but any heat helps while applying vacuum. Peter _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
