Noise from '93 Tempo

This problem has me going. I have a '93 Tempo with a 2.3 w/air. Just under 60,000 miles.
There is a rattling noise coming from the front of the engine at idle.
Almost like sheet metal rattling. If I bring the engine speed up about 300 RPM it goes away.
If I remove the belt it goes away. I noticed that if I disconnect the wire to the alternator it also mostly stops. Just a little ding every 5 or 6 seconds.
Now to what I have tried. I have replaced the idler pulley, the belt tensioner and the alternator.
If I listen with a stethoscope to the A/C compressor, Alt., W/P, and power steering pump I don't hear the noise from any of them. I don't hear the noise coming from the front cover area when I listen there (thinking timing chain). It is loud enough to hear from 50 feet away. I just can't pin point where.
It isn't a new belt on it, but I did change it with a spare I had (the old one I kept when I installed this one).
The embarrassing part is that I have been a truck mechanic for over 36 years now and I can't find a noise. Neither has anyone else where I work.
Has anyone run into something like this themselves? Any ideas?
Thank You for any help you can give this frustrated mechanic.
Bob
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I recall changing a lot of harmonic balancers on these things...
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There is a rattle from the front of the engine at idle. Almost like sheet metal. If I bring the engine speed up about 300 RPM it goes away. If I remove the belt it goes away. I noticed that if I disconnect the wire to the alternator it also mostly stops. Just a little ding every 5 or 6 seconds.
I have replaced the idler pulley, the belt tensioner and the alternator. With a stethoscope I don't hear the noise from the AC compressor, Alt, W/P or PS pump. I don't hear the noise coming from the front cover. I can hear it from 50 feet away. I just can't pinpoint where. Swapping belts didn't help.
Has anyone run into something like this themselves? ____________________________________________________
Different engine (350 Chev) with a similar symptom. A little ching or chirp about every 10 seconds at idle, about every 3 minutes at speed. Couldn't find the source in 400 miles of driving.
Then when starting up after an oil change, sparks started spraying out from behind the W/P pulley, followed by a hail of small bearing rollers. There had not been any W/P leakage - I had checked when looking for the noise - so the fireworks stunned me. I replaced the W/P and the noise was gone.
You could check the W/P by removing the belt and rotating the pully slowly by hand while pushing it sideways in several directions while listening with the stethoscope. Check the other pulleys, too
Good luck.
Rodan.
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snipped-for-privacy@north.wis wrote:

I had the exact same problem with my '87 Tempo, did the same stuff to find the source, and never found it. I kept driving it and sold it, still running quite well, at 210,000 miles. My top Ford tech at the time(he's now working for Ford in Detroit) was stumped, and suspected it was a timing chain issue.
Rob
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Check the a/c compressor clutch pulley. I replaced our's twice on a 91. Rattled like crazy for a time and finally quit. They get alot of road splash and the bearings go out in them. Dealer said it was a common problem. Just a thought. trainfan1 wrote:

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snipped-for-privacy@idirect.ca wrote:

No A/C!
Rob
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I would like to thank everyone for their help.
The more I think about Mr. Warman's idea the more it seems that that might be the problem. It would explain why the noise comes and goes depending on different loads on the belt.
I am not sure how the pulley is attached to the harmonic, if it is spot welded and a couple of welds let loose I can see how this would make the noise.
I am going away for the weekend (close the cabin down for the winter) but will check it out when I get back.
Again Thanks To All.
Bob
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I'm Jim... Mr. Warman was my Dad...

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snipped-for-privacy@north.wis wrote:

You were sooooo close to the problem. It's very likely the harmonic balancer. The rubber shears and the outer ring rattles like crazy at idle. To replace it: Remove the accessory belt(s). Remove the front engine mount (front of the motor) and let it drop down fully. There are 4? bolts on the top and one large nut on the bottom of the mount. Get the nut from underneath. Remove the right front wheel and the inner splash shield. You will have to bend a section of the pinch weld on the front sub frame upward for clearance. You'll know what I mean when you look at it. Remove the bolt in the end of the crankshaft. With a long pry bar, pry the engine down and back as much as possible. Don't pry against the timing cover. The balancer will slide right off, just wiggle it around for clearance to get it out.
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