I am chasing a high RPM (underload only) squeal, sounds like a belt squeal but have replaced the belt and still squealing. Also on decel, there is a slight chirp... Pretty sure its not the alternator bearings it was just rebuilt. There is one toothed serpentine belt that runs the water pump, alternator, and distributor, tensioned with the alternator, and a fixed bearing. see the video, there is no play or movement in the bearing, but it doesnt spin too freely. Let me know what you think. This is on my Jalpa https://www.youtube.com/watch?v=VdWNRQRPV74&feature=youtu.be
A little difficult to discern the noises --- snapping of the latex / nitrile glove vs. the bearing chirp you describe --- from just that recording. I am sure you can hear things much more clearly in person.... I do detect a slight noise that sounds bearing related, though. And, it sounds as though it may be a bit dry (noise resulting from the increased friction). I would do this test --- Spray the bearing generously with WD-40, let it soak in good, and then spin it exactly as you did before. If the noise is gone / greatly reduced, that confirms the bearing is bad.
Just read another thread on a whistle under the same running conditions. Turned out to be an intake whistle. I have a whistle/squeal on my 308i and I thought is was a bearing. Just saying.....
Not sure i would do this. WD40 is 50% mineral spirits. They claim it has other lubricants in it but I would bet it takes more grease out of the bearing that anything else. After all, it is designed to displace water and clean parts.
I use wd a different way. I will spray wd on a suspect bearing as it spins. If the noise goes away that's it. In the video that bearing does not look good to me but feel is definative. When you hold the bearing and rock it does it feel gritty or with stichion? The stichion of a new bearing out of the package is very different from old failed bearing stichion. Also sound travels especially high pitched can really fool you as to source. You could be miles away with a bad AC compressor clutch even. Sometimes a bearing is not really bad but needs the seals removed and new grease packed. Bearings are typically so cheap we just replace them. Then for really expensive bearings there are bearing rebuilders who can get inside those proprietary locked up bearings or do Ferrari wheel bearings for example.
Thank you all. I am not sure what the noise is. The car only has one belt on it (removed AC and air pump). Fortunately the bearing is cheap, so I am just gong to replace it. it could be an intake whistle, just sounds like a belt squeal. could it be valve train related?
I took the car in for my second run at passing CA smog, and made it through (pita). I had an exhaust made up with two huge cats, took it off after passing smog, chirping and squeal totally gone. That exhaust was a bit rusty. That could have been it, or air flow through the cats.... In any case squeal is gone
