burnout8488 Posted November 21, 2013 Report Share Posted November 21, 2013 Out of the blue today, my car started whining a little bit. It was cold, and wasn't too loud, so I took the car on a 10 minute drive to the gym. When I left the gym, the whining was worse, and I drove across the street to the grocery store. When I parked the car, I smelled burning in the cabin, and the noise had gotten pretty loud. Opened the hood, there is smoke coming off of the serpentine belt. I cut the belt and drove the car home. No noise, no smoke… so it's definitely one of the serpentine accessories. The alternator was replaced 3 years ago by the previous owner with a no-name replacement, so I'm not too confident in it. (According to the belt routing diagram, the alternator is supposed to spin CCW and P/S pump CW.) When I spin the alternator counter-clockwise very fast with a drill, it only makes a very faint grinding noise, and it spins up quickly without any abnormal drag. When I spin the P/S pump clockwise with a drill, it is absolutely silent. Are these '99+ pumps known to fail ever? They seem pretty decent. (Made by ZF) I'm just confused as to why there is smoke when everything on the accessory bracket spins so easily. I'd say it's the alternator, but when installed, the noise was extremely loud, and I can't replicate it with the drill at all off the car. Could the clutched alternator pulley be at fault? It locks counter clockwise, and freewheels clockwise. (Correctly) The freewheel action is a bit gritty feeling, but is it supposed to be totally smooth? This is the only thing I can think of that might be the cause of the burning belt…. Hell, maybe the alternator itself is what's smoking?? The tensioner idler pulley spins very freely and I don't think it's the culprit. I checked voltage at idle right after starting the car. It started at 12.5V and over the course of 30 seconds crept up into the mid to high 13s. Shouldn't it immediately hit 14+? Or is this a sign the alternator is definitely screwed up? Thanks for any help.. I need this car Friday and might have to overnight an alternator from FCP later today. Link to comment Share on other sites More sharing options...
MattyXXL Posted November 21, 2013 Report Share Posted November 21, 2013 Could defiantly be the alt, slap another belt on and get a long extension, put the extension on an accessory and put the other end to your ear. When you are on the bad component you will hear the noise the loudest. Hows the AC compressor spinning? Ive seen two instances where the compressor locked up and caused the same issue,One was on my red 854 and I had not used the AC in almost 4 months. Link to comment Share on other sites More sharing options...
burnout8488 Posted November 21, 2013 Author Report Share Posted November 21, 2013 Thanks Matt. I forgot to mention, I got a new belt for diagnosis last night, and used a mechanic's stethoscope and heard the noise on both the P/S pump and alternator. So I'm not sure if it was much help. :-( Seems like the noise just howls through the entire accessory bracket... A/C compressor spins extremely freely, and I definitely had it turned off so the clutch wasn't engaged. At this point I'm considering that maybe the voltage regulator failed and was putting a ridiculously high load on the alternator? It spins fine off the car, but perhaps when it's plugged in the car tries to overload the hell out of it, and it's burning my belt? (Or burning itself internally?) Might have to do this the old fashioned way, trial and error. There's two early S80s at the junkyard, hopefully I can get a PS pump and alternator for diagnostic purposes. Link to comment Share on other sites More sharing options...
MattyXXL Posted November 21, 2013 Report Share Posted November 21, 2013 the alt should have some resistance when spun but should spin free and smooth. If its gritty feeling the bearings are probably toast Link to comment Share on other sites More sharing options...
burnout8488 Posted November 22, 2013 Author Report Share Posted November 22, 2013 Gotcha. The alt itself spins smoothly but the clutched pulley is a bit grindy when I freewheel it. I assume it should have a bit of resistance though. Maybe I'm wrongly assuming that. A Bosch alt from FCP is arriving later today, and I got a P/S pump from an S80 earlier today as well. If the alternator doesn't fix it, the P/S pump will and I'll be on my way. Link to comment Share on other sites More sharing options...
jschaefer7406 Posted November 22, 2013 Report Share Posted November 22, 2013 Alex, Wish I'd read this in time, I have a good alternator from my S70 I could have sent you... Joe Link to comment Share on other sites More sharing options...
burnout8488 Posted November 24, 2013 Author Report Share Posted November 24, 2013 Ah! That would have worked nicely, probably would have arrived earlier than UPS too. UPS ended up delivering the new alt at 7PM on Friday and I was already out of town by then, had to use another car. Oh well, I'll know Monday if it solves the problem or not! Link to comment Share on other sites More sharing options...
Brad850 Posted November 24, 2013 Report Share Posted November 24, 2013 Wow...how long will the car run without a serp belt? Link to comment Share on other sites More sharing options...
burnout8488 Posted November 24, 2013 Author Report Share Posted November 24, 2013 At least ten minutes! Just had my headlights on and no other accesories. Seemed to run perfectly, but I do have a somewhat fresh battery :-) Link to comment Share on other sites More sharing options...
burnout8488 Posted November 25, 2013 Author Report Share Posted November 25, 2013 Problem solved, it was the alternator. The bearings inside were definitely shot, and it was smoking up a storm. The new Bosch reman from FCP works great. This wouldn't have happened if the previous owner just got a Bosch alternator to begin with. The old one was a junk rebuilt alt, probably from China. Barely lasted 50K. Link to comment Share on other sites More sharing options...
survolvo Posted November 25, 2013 Report Share Posted November 25, 2013 Good stuff, glad you got it figured out. Link to comment Share on other sites More sharing options...
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