Klaus is right on! as usual. Here is the How-to on the replacement:
http://www.volvospeed.com/Repair/airpump1.php
I've looked everywhere for the write-up on how to use the VW blower instead of the Volvo one (big savings!) but can't seem to locate it. It's not much different than the instructions except you have to drill out the revits that hold the fan casing together and replace them with some screws if I recall correctly...that's about it. I'll post the link to that with the pictures when I find them. Good luck!
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1998 S70 T5 Emarald Green Metallic, 2004 V70 2.5T Ruby Red, Previous Owner of Black '94 850 Turbo Wagon. My cars have been running so well lately they've got me worried.