Strange Metallic Whirring Noise

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I must be hearing something different.
 
Does this noise occur as some specific point in time in the video? Honestly, I can't hear any whirring on the video... Is it the pinging/ringing/whistling noise? All I hear is the exhaust pulses whacking the inside of the exhaust system. (Nicely finished concrete BTW...)
 
Almost sounds like a couple keys jangling together. If there is nothing under the dash rattling around, and the pipes aren't banging around against the hangers or something then I would spray a little water on the belts and pulleys and such. If that doesn't quiet it down then it would be time for a stethoscope.

Also, there is a short period where it sounds like there could be some piston slap going on, but that isn't the noise your talking about.

Alternators have been known to make those strange erratic noises also.

I had a water pump damaged in a car/deer altercation with just enough damage to cause it to squeak for 40,000 miles before I finally tired of the noise and changed it out.

I know you seem to think the sound originates from the rear, but sound is a wave and the fan can blow it around, other sounds can interfere, and an engine compartment is like a tin can so it will echo all over the place.
 
magnumdart said:
Almost sounds like a couple keys jangling together. If there is nothing under the dash rattling around, and the pipes aren't banging around against the hangers or something then I would spray a little water on the belts and pulleys and such. If that doesn't quiet it down then it would be time for a stethoscope.

Also, there is a short period where it sounds like there could be some piston slap going on, but that isn't the noise your talking about.

Alternators have been known to make those strange erratic noises also.

I had a water pump damaged in a car/deer altercation with just enough damage to cause it to squeak for 40,000 miles before I finally tired of the noise and changed it out.

I know you seem to think the sound originates from the rear, but sound is a wave and the fan can blow it around, other sounds can interfere, and an engine compartment is like a tin can so it will echo all over the place.
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The key jangling sound is from one of the Ultra Flo mufflers. Something has been loose in there for a while. The video isn’t too great. I will see if I can improve on that later today by crawling underneath the car. I am absolutely positive the noise is coming from the rear half of the engine. Definitely have tried pulling belts one at a time, with no change. Nothing under dash rattling; the noise is much more audible outside. Alternator was replaced recently, which had no effect on the noise. Water pump replaced at same time.

I tried swapping distributors (checking for advance spring noise on the old and new one first) this morning, but that had no effect. Drove the car to work this morning again, which is 30 miles one way, mostly highway. Ran fine, no misses, coolant temp great. Same deal with noise though. Fired the car up, was quiet for a bit, then starts making the noise as soon as I pull out of the garage. Keep on my way to work, stop at light and idles for a moment and it goes away. Give it some gas, or begin moving, the noise becomes audible again shortly thereafter and there again at the next light. This has been the scenario for many months/miles it seems.

Thank you all for chiming in on this. Frustrating as hell to me, since I hate uncommon noises like this, or any issues present whatsoever. Sure I can disassemble things in the engine to really see what’s going on, but I am just not completely sold on needing to do that based on the symptoms described.
 
Here is a video I took during lunch. Listen for the metallic noise once the camera is placed under the car:

[ame]https://youtu.be/phdNjTZ57iI[/ame]
 
I listened 5 times and all I can hear is the ringing sound of exhaust pulses hitting inside the exhaust. Sorry, I just can't make out a whirring noise.
 
Are you talking about that REALLY high pitched sound? More like a squeak? That's metal on metal. It'll turn up sooner or later. lol

I have heard throw out bearings and pilot bushings do that if they were dry, but usually, you can tell a difference when you depress the clutch pedal.
 
RustyRatRod said:
Are you talking about that REALLY high pitched sound? More like a squeak? That's metal on metal. It'll turn up sooner or later. lol

I have heard throw out bearings and pilot bushings do that if they were dry, but usually, you can tell a difference when you depress the clutch pedal.
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Yep, the squeak is it, not the rattle. Comes and goes oddly. Sounds like a bearing, but just have a hard time believing it's in the main bearings..Maybe the thrust bearing. Just hasn't gotten much worse over the past 6 months. And no, can't really tell a difference when the clutch is in. Seems as if the thrust bearing could be wormore, but not enough to see any movement when watching the crank pulley while revving the engine. Might take a pry bar to it.

Just keeping it running for a 6 or so months until I build up another motor is my goal.
 
If you were to rev it up and shut it down at a higher rpm would it continue to make the sound until the engine ramped down? That is enough noise that you should easily be able to find it with a stethoscope.
 
Have you tried feeling the oil pan for maybe a windage tray rattle?Or the oil pick-up fell down onto the pan?
But yeah, I watched the video with headphones on about 8 times before the odd noise kindof made itself known.Then I listened a buncha more times.
 
AJ/FormS said:
Have you tried feeling the oil pan for maybe a windage tray rattle?Or the oil pick-up fell down onto the pan?
But yeah, I watched the video with headphones on about 8 times before the odd noise kindof made itself known.Then I listened a buncha more times.
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Yeah I know...it's hard to hear unless right around the car in person. Through the exhaust rattle and typical exhaust note, it's there.

Thought about the pickup but wouldn't oil pressure be way down?

I'll try to fab a stethoscope tomorrow.
 
magnumdart said:
If you were to rev it up and shut it down at a higher rpm would it continue to make the sound until the engine ramped down? That is enough noise that you should easily be able to find it with a stethoscope.
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Pretty sure I've noticed it quiet substantially or not be present at all if I shut down between 1200-1500 rpm. Will verify tomorrow.
 
magnumdart said:
If you were to rev it up and shut it down at a higher rpm would it continue to make the sound until the engine ramped down? That is enough noise that you should easily be able to find it with a stethoscope.
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Shut it down at 1700 rpm and heard the noise spool down with the engine as it ramped down
 
MOPARJ said:
Shut it down at 1700 rpm and heard the noise spool down with the engine as it ramped down
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So was it any easier to discern where the noise originates from without all the exhaust racket? If it is in the back there are not many options. Flywheel rubbing on something maybe. If it is inside the block I guess you could go for it and use the hope for the best method. Most any idea I could come up with now would border on speculation. Maybe the camshaft is working its way out the back of the block. Probably not if the distributor is ok. I'm mostly at a loss right now. Locate the noise and you will more than likely have it figured out.
 
magnumdart said:
So was it any easier to discern where the noise originates from without all the exhaust racket? If it is in the back there are not many options. Flywheel rubbing on something maybe. If it is inside the block I guess you could go for it and use the hope for the best method. Most any idea I could come up with now would border on speculation. Maybe the camshaft is working its way out the back of the block. Probably not if the distributor is ok. I'm mostly at a loss right now. Locate the noise and you will more than likely have it figured out.
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Yep next thing will be up on jacks and listening with stethoscope.
 
I can't hear it either, but I have heard a front timing seal squeel from lack of lube, perhaps the rear main seal is dry, try shooting some lube onto the crank at both ends.

Stethescopes are a tremendous help with things like this, take the needle attachment off, then just point, and follow,, jmo
 
Update on this: Still trying to find the source, all the while I have put another 700 miles on the car with no change in sound, running, or oil pressure. This included a 300 mile roundtrip about a week ago averaging 17 miles to the gallon mixed. I changed the oil after and it was clean with no metal shavings. I was able to isolate the sound to the lower front right area of the engine. I pulled the fuel pump and checked it and all looks well, with no abnormal witness marks on the pump arm. The eccentric seems ok as well. I pushed on the Cloyes double roller chain which has been in since the rebuild years ago, and there is less than an 1/8” of slack. So unless there is far more slack on the other side, I can’t see it hitting the inside of the timing cover and its more of a squaking type of noise anyways. Water pump is fine. With that said, I am still searching for the culprit. Noise comes and goes and seems to fade away after idling for a bit. I have also noticed that the easier I drive, the less frequent the noise is present. Unless I run across the cause, I have decided to just “run it” and see how things go.
 
Just wondering if you have pulled off the alternator belt and run it for a bit to see if this goes away?
 
nm9stheham said:
Just wondering if you have pulled off the alternator belt and run it for a bit to see if this goes away?
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I have yes. In fact, I removed all of them. The alternator was replaced a few months after the noise began. I'm starting to question of maybe there is something rubbing on the front of the timing cover behind the balancer.
 
Or the oil slinger on the back of the timing cover. That is not unheard of. Check to see if the balancer is pulled all the way tight to the crank; the bolt takes 135 ft-lbs or so. If the balancer is not pulled in fully, then the slinger can move around.
 
Could be the slinger. I think I'm going to swap to a new balancer. The current one has about 200,000 miles on it and wasn't replaced at the last rebuild 8 years ago. I will look at the bottom timing cover seal to see if it's dried out and maybe contributing to the noise.
 
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