This forum has been a great help to me, but just recently I am experiencing (seems to be happening a lot as I just hit 281k miles a few days ago) what seems to be a gravely, rough clunking noise eminating from the alternator case. In the video, I mention the exhaust manifold, but I ruled that out.

TL;DR - Weird noise coming from the alternator/exhaust manifold area. Videos at the bottom of the post.



I took it into my local shop, who I've had great service with. Without dismantling the engine block, the mechanic there said he would at least look it over and listen. He said it's very hard to tell, but thinks it's a broken crank or even a loose bearing in the engine. It sounds like something is clanking around. He said when I do my next oil change, to slowly remove the bolt and wipe it off with a white paper towel and check for metal shavings, which would confirm his suspicions. He said it vvery well could be with the alternator, but without servicing the vehicle he wouldn't be able to give me a straight answer, which is understandable. The car drives fine, NO PROBLEMS, whatsoever with performance of the vehicle. It really runs like a champ.

Upon further investigation at my house, I decided to do a old 'engine-ears' trick my dad showed me. I took a long screw driver, held the handle to my ear, and put the metal end on the alternator case. It definitely seems like the sound that I hear, correlates with the vibrations from from the alternator. I have not put a multimeter on the battery or alternator yet, I will do that this Friday when payday rolls around.



Could this be my alternator failing, maybe the brushes or bearings inside of it are failing, maybe the crankshaft pulley might have separated, the rubber dampener, or is this probably a more concerning issue with the engine internals? I know it's hard to tell by watching a video and just listening to the sound, but it's worth a try.

I have two different videos, hopefully will narrow down the noise location.


<p><a href="https://vimeo.com/161870064">91 Honda Accord Noise</a> from <a href="https://vimeo.com/user50872020">Darin Koehler</a> on <a href="https://vimeo.com">Vimeo</a>.</p>


<p><a href="https://vimeo.com/161882205">Noise Problems, part 2</a> from <a href="https://vimeo.com/user50872020">Darin Koehler</a> on <a href="https://vimeo.com">Vimeo</a>.</p>



The noise you hear in my video, is VERY similar to this noise, and it turned out to be his alternator.

 

Remove the belt. Start it up. Listen for the sound.

 

Didn't know if it would cause problems running the car without the belt, will get back to you. Thanks

 

I am leaning towards bad bearing in alternator. It's not a crank or engine bearing problem. Belt off test should give the answer......

 

It was definitely the alternator. Didn't know it was that simple. I'm still learning.


Thanks, it's the alternator.

 

Glad we could help