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Discussion Starter · #1 · (Edited)
Loud whine coming from the engine bay. At first I thought it was the alternator failing so I replaced it, still same noise. If you get close it sounds like it is coming from the back of the engine, near the regulator. Replaced the regulator and same noise. Coil is fairly new. Alternator is pertronix. Not sure what else it could be. Power steering? Guess I can take the belt off and see if it stops. Everything is funtioning normally. No charge issues. Car runs great except for this insane noise. Also I have electronic fans but no noise from them. Ill try and post a video once I figure out how to get this site to allow me to upload


 

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Loud whine coming from the engine bay. At first I thought it was the alternator failing so I replaced it, still same noise. If you get close it sounds like it is coming from the back of the engine, near the regulator. Replaced the regulator and same noise. Coil is fairly new. Alternator is pertronix. Not sure what else it could be. Power steering? Guess I can take the belt off and see if it stops. Everything is funtioning normally. No charge issues. Car runs great except for this insane noise. Also I have electronic fans but no noise from them. Ill try and post a video once I figure out how to get this site to allow me to upload
You'll need to upload it to youtube and then post the link.
 

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I had a metal torque converter cover that was rubbing on the flywheel, or converter IDR, that sounded similar to that. Sounds like sheet metal on metal, starter hung engaged, or wind (vacuum or pressure whistle).
 

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Discussion Starter · #9 ·
If it helps, the noise does not decrease or increase with rpms. Same constant whine. That's why I thought it would be electric. I'll start probing for some vacuum leaks to start.
 

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Get a long screwdriver or automotive stethescope and go to work. I'd concentrate on the distributor judging by the sound. The other comments of starter/dust shield have merit as well. Sounds like an alternator bearing, but you checked that. Not a vacuum leak as it would go away when you rev the engine.
 

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First listen it sounded more like a whistle to me, which steered me towards a vacuum leak of some kind. Try a stethoscope to pinpoint the source and maybe disconnect and plug/cap every vacuum connection at all points on the intake and carb to see if that stops it. Other possibilities, just spit-balling here:
  • Shaft bushings in the distributor going away
  • Distributor gear end play too tight and allowing the gear face to rub on the distributor body.
  • Distributor gear extremely worn (not sure it would sound like that though)
  • Distributor rotor squealing "somehow"?
I'm with GeeTee that a vacuum leak would go away with RPM, but...
  • Leaking intake manifold gasket
  • Cracked vacuum line fitting
  • Cracked carb base plate
  • Extremely worn carb throttle shaft(s)
When you said it doesn't change with RPM... Did you mean it doesn't go away? Does it stay the same pitch and/or volume?

Bear
 

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Discussion Starter · #13 ·
First listen it sounded more like a whistle to me, which steered me towards a vacuum leak of some kind. Try a stethoscope to pinpoint the source and maybe disconnect and plug/cap every vacuum connection at all points on the intake and carb to see if that stops it. Other possibilities, just spit-balling here:
  • Shaft bushings in the distributor going away
  • Distributor gear end play too tight and allowing the gear face to rub on the distributor body.
  • Distributor gear extremely worn (not sure it would sound like that though)
  • Distributor rotor squealing "somehow"?
I'm with GeeTee that a vacuum leak would go away with RPM, but...
  • Leaking intake manifold gasket
  • Cracked vacuum line fitting
  • Cracked carb base plate
  • Extremely worn carb throttle shaft(s)
When you said it doesn't change with RPM... Did you mean it doesn't go away? Does it stay the same pitch and/or volume?

Bear
It stays the same pitch and same volume, even all the way up to 5k rpm. Which makes this very weird. If this was any vacuum issue or bearing issue anywhere in the engine you would think the pitch or volume would change at all.
 

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If you're thinking vacuum leak did you spray water or carb cleaner around to see if it changes? And wouldn't it run bad if it had a leak that bad, it sure is loud. It still sounds like metal like a bearing but than the pitch should change with rpm. You said you changed the alternator but did you ever run it without the belt, same with the water pump and p/s pump...process of elimination.
 

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Loud whine coming from the engine bay. At first I thought it was the alternator failing so I replaced it, still same noise. If you get close it sounds like it is coming from the back of the engine, near the regulator. Replaced the regulator and same noise. Coil is fairly new. Alternator is pertronix. Not sure what else it could be. Power steering? Guess I can take the belt off and see if it stops. Everything is funtioning normally. No charge issues. Car runs great except for this insane noise. Also I have electronic fans but no noise from them. Ill try and post a video once I figure out how to get this site to allow me to upload


Just a wild guess. I’m wondering if you have a loose pully that is rattling … it sounds in the video like a rattling sound to me. I would start off by taking all the belts off to remove any possibility of pulleys or related parts. It does sound like it’s coming back in the rear of the engine compartment. That could be echoing from the engine compartment or isolated to the back of the engine. If that’s the case snd you have identified it truly coming from the rear of the motor then as bear said , I would look at the related parts to the distributor and the possibility of a loose bolt on your fly wheel or related parts. But I’m 72 and hard of hearing. Lol the best of luck for finding your issue.
 

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Discussion Starter · #20 ·
So, was able to poke around at it for a bit.
No vacuum leak. Checked every inch of the carb, intake, vacuum lines etc. Rpms to not change when introduced with starting fluid, etc.

No pulley issues. Checked by removing the belts and running the engine.

Starter is not binding on the flywheel. Visual inspection. Flywheel itself seems fine. There was a bolt that was slightly loose but nothing major.

Distributer is not the cause. Checked by switching in another old one I had laying around.

Due to sound being at the back of the engine, maybe transmission issues? Shifts and runs fine. Again the noise stays the same during all rpms and either in park or idle. Also the noise does not start until the engine is warmed up, about 10 minutes after initial startup.
 
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