Whining noise from outer space

[Sammy]

Hi there,

maybe someone can help me with this issue.

I own my 63 CdV for over 13 years now and sometimes - mostly in summer - 
when driving I hear a whining noise. 

Changed transmission fluid several times, rear bearings, front bearings, even changed the 
complete front brake system. No change. 

The sound is not depending on rpm of the motor, it's a mystery. 
And it doesn't appear every day, some months I hear nothing.

Did anyone had this problem before? 
I add an MP3 I recorded of this.

Thanks and stay healthy,
Sammy from Germany

[3a93lc0athkg1]

I had the same thing two years ago and it drove me crazy trying to figure it out.  Thought it was something big but it turned out to be something simple:  A leak in the intake manifold gasket.  At times, the leak would make a high pitched whistling sound, very sporadic.  New gaskets took care of it no problem.  Good luck!

[Kurt]

Lee, Same here. I could have sworn it was coming from the carburetor so I rebuilt the carburetor. It would still happen after that. It was very random. I was then convinced that my carb was worn out and was ready the replace it with an Edlebrock. Before I did that, the noise started happening more often. This allowed me to properly track it down to a leaky intake gasket. I had had the intake off before years ago to replace the valley pan gasket. The replacement intake manifold gaskets I used at that time were very thin metal gaskets. This time I located thicker gaskets with the help of Jason (”Best RS663G for 429, RS663G1 for 390; use a Best 14046 or 14046E for intake gasket. Intake gasket is thick, not metal”) Problem solved!

Sammy, I don't know if this is same problem you are having, here is a short video of the noise my car made. It seemed to be related to engine temperature. I assume the gap would open up when the engine was hotter. While I would investigate, it would cool off then stop whistling. Very tricky to troubleshoot.

https://photos.app.goo.gl/qNiPfYzJfzTZFkwU7

Whistle

[Sammy]

Where did you buy the parts? 
Is it easy to disassemble the intake manifold?

[Kurt]

Very easy to take off the intake manifold. If you find out the problem is leaking gaskets, here is where I got mine:

https://vintagecarburetorsandgaskets.com/shop/intake-manifold-set-1...

[Sammy]

Thank you. 
And these are more reliable than the standard metal type?

[Sammy]

Thanks for all your replies. 

I don't think it's the intake or carb, because it only appears when the car is moving. 
Like I wrote it's not rpm dependent, so I think it has to be something with the drivetrain or transmission. 

[Sammy]

Sounds and leaks are the most difficult problems on cars, I know. 
Didn't want to bother or upset you by asking my questions, but it seems like I did.
Sorry for that. 

I don't have the possibility to lift the car and do it by myself, everything underneath 
my CdV has to be done at a local garage.
I got some skills, so work without lifting is mostly done by me.
The mechanics at the garage are not very familiar with american cars, especially not Cadillac, so every work is explained by me and they do it. 

That makes it more difficult and of course expensive just trying something

I tested the carb and manifold today for leaks with a special carb spray - no leaks. 
So I'm pretty sure it's not the carb. 

Next would be the carrier of the drivetrain, hope thy guys at my shop can do this.

What about the last bearing / seal where the propeller shaft goes into the transmission? 
In the shop manual I read something about the governor that can cause a whining sound.

[3a93lc0athkg1]

Mine was the same way, had a metallic screeching sound like a bad bearing or transmission issue.  Came and went, not RPM dependent.  Never when motor was cold and rarely when idling - would start softly after about 1 mile of driving and gradually get louder and louder.  When I would pull over to inspect, it would mysteriously stop.  So I was convinced it was transmission.  So relieved when it was just the intake gasket.

[3ft7bqmb7dryo]

Pull the drive shaft and check the carrier bearing. 

[Jason Edge]

Vintage Carburetors & Gaskets Added to Parts Supplier page. I have ordered from them before and are highly recommended.

[1rbyytz548v0n]

You can troubleshoot a vacuum leak as others have described with water, or better yet squirts of starting fluid which will suddenly increase your rpms.  I would check it with a vacuum gauge to see how much vacuum you have.  My guess is that you should troubleshoot the a/c system for your leak not ruling out your compressor since you mentioned "mostly in summer."  Is the a/c running when you hear the noise?? I am sure you have already eliminated belt noise when the system is on, as well as water pump bearing noise under belt pressure.  I use a stethoscope (cheap one) to look for noises, or even a long thin screwdriver if you are careful.  I don't believe in ignoring a recurring noise until it breaks, usually costs more to fix it or get towed in.  Good luck.

[Sammy]

Hi Douglas, the spray I use is doin' exactly the same thing. 
But no rpm change, so I guess there's no leak.

AC is off, I already tested all these things. 
The sound is never heard when the car is standing still, only when moving.
And it stays the same when I put it in "N" while driving and push the throttle.
So I can tell for sure it is not rpm dependent.