Really really loud noise - Bad Alternator?
11-10-2012, 01:35 PM
#1
Really really loud noise - Bad Alternator? Hey guys, I have a loud "squeaking" noise coming from my engine bay. It was RPM-related so I guessed it was related to my belt. I got some belt dressing and sprayed it around here is what I found:
1) If I spray it away from the Alt, it doesn't do anything as far as stopping the sound.
2) If I spray it right on the Alt pulley it stops the squeak immediatly, but only for a split second.
3) That battery charge looks fine all the time.
4) It seems to be a little more difficult to start up (cold) lately.
5) The battery is a 2 year old Optima.
Bad Alternator???
1) If I spray it away from the Alt, it doesn't do anything as far as stopping the sound.
2) If I spray it right on the Alt pulley it stops the squeak immediatly, but only for a split second.
3) That battery charge looks fine all the time.
4) It seems to be a little more difficult to start up (cold) lately.
5) The battery is a 2 year old Optima.
Bad Alternator???
11-10-2012, 02:21 PM
#2
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Lots of things can cause belt squeak on these cars. It could be the alternator, or the tensioner or idler pullies. Or even an old belt, or one of the other accessories.
I'd try taking the belt off and spin each of those pullies by hand to see if any are grinding/binding/making any sort of noise. You can also check for pulley wobble to indicate bad bearings.
I'd try taking the belt off and spin each of those pullies by hand to see if any are grinding/binding/making any sort of noise. You can also check for pulley wobble to indicate bad bearings.
11-10-2012, 03:18 PM
#4
Ok, took the belt off. Belt looks to be in good shape. I spun the Alt pulley and hear a slight ticking sound, and if I spin it a certain direction from under the car where I can get a good hand on it, I think I heard a faint squeak. Probably it, right?
Anything I can do short of replacing it? It seems to charge fine still...
Also, the tensioner pully spins liberally, is that what it's supposed to do? I thought that they were only supposed to spin around once or twice when you hand-spin them?
Anything I can do short of replacing it? It seems to charge fine still...
Also, the tensioner pully spins liberally, is that what it's supposed to do? I thought that they were only supposed to spin around once or twice when you hand-spin them?
11-10-2012, 06:06 PM
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Ok, took the belt off. Belt looks to be in good shape. I spun the Alt pulley and hear a slight ticking sound, and if I spin it a certain direction from under the car where I can get a good hand on it, I think I heard a faint squeak. Probably it, right?
Anything I can do short of replacing it? It seems to charge fine still...
Also, the tensioner pully spins liberally, is that what it's supposed to do? I thought that they were only supposed to spin around once or twice when you hand-spin them?
Anything I can do short of replacing it? It seems to charge fine still...
Also, the tensioner pully spins liberally, is that what it's supposed to do? I thought that they were only supposed to spin around once or twice when you hand-spin them?
It ended up being my tensioner pulley. Like yours, it spun almost indefinitely with one twist by hand. They should only spin a little bit, as you mentioned. So I would start by replacing that.
11-10-2012, 07:25 PM
#6
My alternator made a faint squeaking sound when turned by hand as well. But that was not the source of my belt squeak.
It ended up being my tensioner pulley. Like yours, it spun almost indefinitely with one twist by hand. They should only spin a little bit, as you mentioned. So I would start by replacing that.
It ended up being my tensioner pulley. Like yours, it spun almost indefinitely with one twist by hand. They should only spin a little bit, as you mentioned. So I would start by replacing that.
Thanks fellas!
