[Possible?] Alternator Belt needs replacing?

[Anderson]

[I copied this over from an email I sent to my mechanic...but BOY am I having a night...]

I'll start off noting that I'm safely in Florence, SC.  This is a bit of a long writeup, but that's because there are a few pieces to the puzzle and I'd like advice on where to go next.

Starting off with the "main event", a bit north of Savannah (maybe 45 miles into SC) I heard an odd buzzing sound from in front of me (presumably in the dash or in the engine compartment).  My initial instinct was to cut the fan (I did so, but it had no meaningful effect).  I cut the radio and unplugged the USB cable charger from the cigarette lighter, but the sound continued.  At several points, the lights seemed to flicker a bit, and at a few points I smelled a "smoky" smell (I also think the cabin "smoked up" a little bit on those occasions, but I'm wary about attributing that to anything more than condensation.  I basically made it the rest of the way to Florence sitting on the edge of my seat.

At one point (somewhere north of the I-26 interchange), I heard (and felt) something bounce under the car.  It sounded like something "heavy" fell off, but I have no earthly idea what it could be.  At this point, I would note that I had heard what sounded like something falling off down outside Orlando (this item sounded metallic; as such, when I next stopped for gas I checked to see if I'd lost a trim piece).

Anyhow, I shot some video on my approach to my hotel: The buzzing sound continued and seemed to correlate with my speed (it seemed to get "slower" as I slowed down).  When I came to a stop, I heard a lot of squeaking (i.e. more than just slightly squeaky brakes), and the "GEN" light came on.

There are a few more pieces to the puzzle:
-I took the attached photo yesterday afternoon (before leaving Orlando) since it looked like whatever that is was a bit "out of place", but I don't know what it could be.
-The valet at the hotel noted that the GEN light came on when he was getting out of the car, but IIRC that's one of the lights that "always" comes on when I open the door so I didn't think much of it at the time.
-When I was approaching Tallahassee, I ran over...well, something plastic that I couldn't avoid.  There was no immediate impact on anything, so it didn't come up until now.

My best guess is that the alternator belt got affected (somehow) when the steering belt broke (amid the AC compressor failing).  The AC compressor has been unplugged, so that shouldn't be much of an issue.

[TJ Hopland]

What car are we talking about here?   From the photo looks 70's or 80's?   I can't quite tell what we are looking at under the car in the photo.  From that angle I don't think we should see anything hanging down and it looks like we are looking at a hard metal line and some wires?  Hard lines that size would be fuel related and I don't think there was any factory wiring outside the car in that area. 

Assuming this is a mid 70's car there would be 2 or 3 belts.   Power steering and AC would be one or a pair of belts depending on the year.  You mention an AC failure?  So was a shorter belt used to bypass the AC compressor?   That's a reasonable fix and even listed in the manuals for non AC cars.   This just connects the power steering to the crank, nothing else.   IF the AC was still in place just adds in the AC.  Has nothing to do with the alternator or water pump.

2 or 3 belts depended on if it was a AIR or 'smog' equipped car, most in the 70's were so we will assume 3 belts.   One belt went crank to water pump to smog pump.   Water pump had a 2nd groove when then had the 3rd belt that drove the alternator.   If there is no smog pump the belt goes crank - water pump - alternator.   You can't just bypass the smog pump, they changed the alignment of things to prevent it from being that easy.   

Perhaps the noise you were hearing was the bearings in the smog pump failing?  Eventually causing belt to start slipping which could result in some smell and smoke?  And the alternator slowing down?   It doesn't seem like you lost it completely because if you did you would have also lost the water pump and fan so you would have overheated and boiled over in a couple minutes. 

Belts and pulleys don't really hang down on these cars so I don't think its that likely that hitting something on the road would damage a belt.   If a belt driven device was failing it could damage the belt and as its coming apart it could literally be whipping around into things making a lot of noise.   It could also whip into other belts and cause issues with the other belt.

I'm not sure how the junk hanging down in the photo would relate to any of this stuff unless its an 80's car which did often have a hard 'smog' line down to the cat converter.   Damaging that line would not cause the pump to fail so I still do see a relation.  The 80's had a similar belt layout but added in a vacuum pump.   

What usually kills the smog pumps is a check valve near the alternator fails and lets exhaust back flow all the way down to the pump.  The hot and corrosive exhaust gasses get into and kill the bearings in the pump.  Check valve is really easy to test.  Pull the hose off that loops over the alternator and start the engine.  If you feel exhaust coming out that nipple thing on the hard pipe its failed.  That fitting is the valve.   Same valve was used on a lot of GM products so I assume they are still available.       

[bcroe]

The alternator light should NOT come on.  Find out what that is about,
and perhaps fix the problem. 

One reason my alternator light came on, was failure of one
of the 3 phase rectiiers.  Lots of other possibilities.  Bruce Roe

[TJ Hopland]

Curious to hear what they found and also what year this is.    I wasn't clear from the story if he was home yet or still 'on the road'.   If he is still out maybe its talking longer to find someone that can look at it and deal with the logistics of possibly not having any other car to drive while this one is down.

[Anderson]

Apologies for the delay in updating...I got home stupidly late that night.

(1) It's a 1970 Eldorado...so no smog pump ;-)
(2) It turned out to be shot alternator bearings, which went so far out of whack that they were messing with the belt (hence the squeaking).  There was still a "headlight flicker" afterwards, so we're also checking those connections.
(3) We think the picture just indicates that a bracket was knocked loose.  That's being dealt with as well.