Alternator whine on nearly new alternator (not speaker whine) - any ideas?

[MichaelSE]

I recently replaced my alternator with a new one to fix the flickering lights issue. This one fixed the problem, charges the battery just fine, but has developed an extremely annoying high pitched whine that follows rpm. It's not coming through the speakers, it's coming from the alternator itself. It's much more pronounced on a cold start, but I've heard it a few times at operating temperature.

If I disconnect the battery charging cable on the back of the alternator, the noise goes away.

Of course it decided to start whining a month after I bought it, so my return period is closed. Does anyone have any ideas how to fix or diagnose this, short of dropping another $140 on another alternator? So far I have checked the tightness of all electrical connections I can find, and they're all good. I've sprayed the alternator with quick dry electronic cleaner. No luck so far.

 

[sk1dm4rk]

What brand/where did you get it? Even though you are past the return period, if it is defective they should replace it assuming it is under warranty.


Regards,

Mark

 

[MichaelSE]

Hi Mark,

It's a Remy alternator, and I bought it on Amazon. I've spoken to a customer service rep, they told me that auto parts returns or exchanges past the window are generally never approved, but I'm waiting to hear back.

 

[sk1dm4rk]

Yeah. Amazon may not be the entity that does the exchange. You may need to reach out to Remy to see what the process is for exchange.

Is this the one? https://www.amazon.com/Remy-91614-100-New-Alternator/dp/B003YMTLPG

If so, it says this:

Warranty & Support
Warranty, PartsartsWarranty, Labor:Limited lifetime for noncommercial use. 12 months for commercial, industrial or off-road use

Manufacturer’s warranty can be requested from customer service. Click here - https://www.amazon.com/gp/help/customer/display.html/ref=help_search_1-1?ie=UTF8&nodeId=201596310 to make a request to customer service.

It looks like you have a lifetime warranty.

Hope this helps.

Regards,

Mark

 

[MichaelSE]

It certainly is that one. I didn't even think to check the product description again. Thanks so much! Let's see if Remy stands by their warranty claim.

 

[sk1dm4rk]

You're welcome. Good luck!

Let us know how it goes.

 

[iamdub]

Generally, a poor ground causes alternator whine. A poor ground is very difficult to have with an alternator since it's case (that bolts to the engine, etc.) is probably the best grounded part on a car. So, I concur with saying the alternator is defective from a failed diode/rectifier bridge/open circuit.