She started fine. Was driving around for a while when the engine started making a loud noise. Sounds like, imagine if you will, a bunch of screws in a plastic ball being shaken around. I guess like a rattling. I took a video but can’t upload it here. Thoughts?

Hello again, I would check the water pump, and or the alternator. 

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Thanks, I appreciate the suggestions. I have an appointment to take her to be looked at in two weeks.

Have you looked to see if there IS a plastic ball of screws flopping around in it? (sorry....but I have seen such things)

If you have a youtube channel, upload the video there and post a link here. If you do not have a youtube account, you can email the video to me and I will post it here for others to listen to. You can click on my profile and get my email address. 🙂

A rattle as you describe could be anything from major engine damage, to a minor exhaust rattle...hard to say without actually hearing it.

Joel Adams
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Thank you, Joel. I emailed it to you. Appreciate it!

Got it! Will work on getting it up today. 😉

Joel Adams
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Thank you, Joel!

HERE's the link for the sassie noise video. My opinion is that it is the A/C compressor pully bearing. Other possibilities are the water pump(is it leaking?), or alternator. My money is on the pulley bearing. Does the A/C work? If son, does the noise CHANGE when you turn the A/C on?

After watching it a couple more times, it looks like the A/C compressor might be new? Even so, it could still be the noise. My second choice is the alternator. You can place your hand on the alternator(cold, on startup!) while running to feel that noise if it IS the alternator. 😉

annnnnd another thought(it's early....gimmie a break...🤣)....it COULD be the harmonic balancer inertia ring has come loose from the hub, and scraping on the timing chain cover.....

Joel Adams
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Hi, I had a couple alternators make the same sounds. Take the belt off and start the car. It will isolate the sound. It's my guess the bearings are shot. Also with the belt off, turn the pulley by hand. Feel for roughness or looseness in the shaft. 

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Yeah, that does sound like a pulley shaft noise.

When I first heard the noise I thought A/C drive clutch - I seem to recall ours made a similar sound many years ago when I think it was failing.

I tend to think that alternators make more of a constant scream/screeching sound rather than a rattle?  I maybe wrong.

But, like Joel I also have come to think that it might be the start of the harmonic balancer out section moving and touching the timing chain cover.   I've seen that happen, although the problem was addressed before the pulley hit the cover.  

I'd also be tempted to check all the nuts on the fan to pump connection and maybe give the fan itself a bit of a "shake" - when its not running of course!😀   Likewise, check the P/S pump bolts for tightness, they don't all need to be tight to hold it in place.

Y’all are great! Thanks for all of the input and suggestions! A/C compressor is new. One of the “fixes” after I got her. I’ll still try the troubleshooting Joel mentioned. I’ll also check out the alternator to see if I feel the noise. That’s about the extent of my skills. lol I’ll keep ya posted. She goes in 1 Nov for diagnosis. 

Whichever culprit it turns out to be, it is NOT an engine noise, so no worries about engine damage, imo. It is one of the accessories...A/C pulley bearing, alternator, water pump, or power steering pump....or harmonic balancer. Should be a fairly easy fix, in any case. 🤠

Joel Adams
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Looks like your air conditioner pully is not lightened up correctly which will cause bearing damage

It really sounds like a scraping noise to me which could be, as possibly suggested earlier, that the outer ring on the harmonic balancer has moved and is contacting the timing chain cover slightly. 

1973 L-82 4 spd