Volvo Repair: Squeal noise when starting, volvo 240 dl, crankshaft pulley

Question
QUESTION: When I start my 1987 Volvo 240 DL I hear a squealing noise. I have replaced all the belts and I still have the noise. It seems to be comming from the AC belt ( it doesnt happen with the belt removed). The AC works fine. Is there some kind of bearing that the pully for the AC rides on and is it easily replaced or would it require a new AC compressor?

ANSWER: Either the battery is discharging or weak, or the AC belt needs to be tighterned up. Check the belt tension and then have the charging system tested

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QUESTION: The charging system checked out fine. The belt has about 1/4 inch of deflection in it. Is that tight enough? Thanks.

Answer
The belt may be out of alignment.There are rubber bushings that the AC/alt, and PS pump brackets mount to.When they wear, the alignment of the belt can be thrown off.Also check the crankshaft pulley,there is a rubber dampner in the pulley that will seperate the outer portion of the pulley.Does the noise change when you turn the AC on/off?That may indicate a internal compressor problem.