I had a rebuilt alternator installed on Thursday and for the past two days when I start up the car there is a high pitch whine coming from what I believe is the alternator. Do some rebuilt alternators make noise when charging the batter after start-up? The alternator has a 3-year warranty and I’m going back to the shop tomorrow.
Maybe, maybe not. If the pulley is misaligned or the belt too tight you could have a whine. Any good alternator is NOT supposed to whine.
If it does, it is likely to fail soon. I would take it back and expain it and take the installer out for a spin.
You are doing the right thing taking it back to the shop. A bad diode in the alternator also may cause a high pitched whine. I’ve had this high pitched whine in the alternator and within a couuple of days, the alternator fails.
Rebuilt parts turniing out to be no-good when installed is a very common thing here. It isn’t normal to hear a whining sound from the alternator. It might be the belt tension wasn’t adjusted correctly though. Did they put a new belt on, or re-use the old one?
Actually, I had a friend listen to my car and it wasn’t the alternator at all. It’s my secondary air pump which sits right beside the alternator. The pump cycles on and off when I start the car and then I don’t hear it the rest of the drive. The alternator is working like a little champ.