The serpentine belts on the S4 spiders seem to be problematic, and even when perfectly aligned, start to make noise shortly after a fresh belt is installed.
Take a close look at the bushings that mount the A/C compressor. The tend to 'sag' or take a 'set' with age, and will throw the belt alignment off. There are also shims behind the P/S pump, it is imperative that they be installed in the same position as they were, if the pump is removed for any reason. If you are unsure of any of this, the only way that I am aware of to check the alignment is with one of these: http://tinyurl.com/36pkoqs It's kind of awkward to use, especially in tight quarters, but I am not aware of any other way. I've never had any luck using a straight edge to check pulley alignment. I think the key is to mount it on each pulley in turn, and if they are all lined up correctly, then the beam projected will hit each one in the same place. IOW, it is not enough to mount it on one pulley and check its alignment to the others alone. Jeff -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Wednesday, June 09, 2010 5:08 PM To: [email protected] Subject: [alfa] S4 spider serpentine belt Looking for suggestions to solve a very noisy belt. Here is some background info: 1992 Spider, ~130K miles. It is quiet at a cold start, but gets very noisy when at normal operating temp. It's not a slight chirp, but more of a constant screech. Very noisy at idle, when engine speed is increased noise goes away (or is masked by engine noise). Noise seems to originate near the A/C pulley / idler wheel area. Pulleys seem to be in correct alignment, not sure how to verify this. The belt is fairly new. It was adjusted by my mechanic and was OK for a while, but noise has returned. The idler wheel is fairly new also. A/C compressor is original, was converted to R34 a few years ago. Seldom used. The car is driven maybe 1X per week. Any suggestions are appreciated. Thanks, Marc -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected] -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
