Descriptions of this job:

http://swedishbricks.com/faq/fanmotor.html
http://www.sonic.net/~zipzippy/volvo/blower%20motor.html

e.g.
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From: mike@oracorp.com (Mike Meador)
To: swedishbricks@me.rochester.edu
Subject: 240 Blower Motor Fix

I pulled the center console-radio-heater-etc plastic panel off and pulled the underlying metal frame back enough to provide minimal access to the blower motor case. I then used a Dremel tool and knife to cut two 1" sq holes in the plastic motor case:

see this link for drawing: http://swedishbricks.com/faq/fanmotor.html

The holes provided a reasonable view and access to the motor shaft and bushings. I first applied some penetrating oil followed up with spray-on foaming white grease. (Any oil that would eventually flow back into bushing-shaft junction would probably work.) I alternated applying lubricant with running the fan on low speed for 6-8 times.

I then cleaned up the housing surface, applied a couple layers of duct tape to cover the holes, and put everything back together. No more loud squealing!
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