Alternator maybe?
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
Alternator maybe?
2001 LS1 55,000 miles (about 30,000 miles on this alternator - GM Valeo Replacement under warranty a few years ago).
I just finished my workout at the gym, got in the car, started the engine and heard a low-pitched "roar". Looked down and the Voltmeter/DIC had dropped to 11.7. At first I thought maybe I had thrown a belt, but it was OK.
I opened the hood and could not tell where the roar was coming from, but there was a smell something like burning rubber or plastic I think - no smoke. I made it down the street to the local O'Reillys and they could not tell where the roar was coming from either. They hooked up their analyzer and it read 12.1 (which they said was low).
Battery is only 4 months old Die Hard P4 Platinum and it reads 14.63V - so I think it is fine.
Made it home about 2 miles with the Voltage gage reading about 11.7 all the way (usually is just under 14 and I watch it like a hawk every time I get in the car).
So, any ideas what my problem is? Think I need a new alternator or could this be something else dragging the voltage down that "roars"?
I just finished my workout at the gym, got in the car, started the engine and heard a low-pitched "roar". Looked down and the Voltmeter/DIC had dropped to 11.7. At first I thought maybe I had thrown a belt, but it was OK.
I opened the hood and could not tell where the roar was coming from, but there was a smell something like burning rubber or plastic I think - no smoke. I made it down the street to the local O'Reillys and they could not tell where the roar was coming from either. They hooked up their analyzer and it read 12.1 (which they said was low).
Battery is only 4 months old Die Hard P4 Platinum and it reads 14.63V - so I think it is fine.
Made it home about 2 miles with the Voltage gage reading about 11.7 all the way (usually is just under 14 and I watch it like a hawk every time I get in the car).
So, any ideas what my problem is? Think I need a new alternator or could this be something else dragging the voltage down that "roars"?
Melting Slicks
Joined: Jun 2012
Posts: 3,163
Likes: 6
From: Oceanside California
Did this "roar" continue after the drive? The only thing I know of that makes a louder noise when you start up and stays on till operating temp is the air injection system. But that doesn't sound like your issue... Shouldn't have anything to do with volts anyway...
Team Owner
Joined: Jan 2007
Posts: 29,063
Likes: 1,839
From: cookeville tennessee
2001 LS1 55,000 miles (about 30,000 miles on this alternator - GM Valeo Replacement under warranty a few years ago).
I just finished my workout at the gym, got in the car, started the engine and heard a low-pitched "roar". Looked down and the Voltmeter/DIC had dropped to 11.7. At first I thought maybe I had thrown a belt, but it was OK.
I opened the hood and could not tell where the roar was coming from, but there was a smell something like burning rubber or plastic I think - no smoke. I made it down the street to the local O'Reillys and they could not tell where the roar was coming from either. They hooked up their analyzer and it read 12.1 (which they said was low).
Battery is only 4 months old Die Hard P4 Platinum and it reads 14.63V - so I think it is fine.
Made it home about 2 miles with the Voltage gage reading about 11.7 all the way (usually is just under 14 and I watch it like a hawk every time I get in the car).
So, any ideas what my problem is? Think I need a new alternator or could this be something else dragging the voltage down that "roars"?
I just finished my workout at the gym, got in the car, started the engine and heard a low-pitched "roar". Looked down and the Voltmeter/DIC had dropped to 11.7. At first I thought maybe I had thrown a belt, but it was OK.
I opened the hood and could not tell where the roar was coming from, but there was a smell something like burning rubber or plastic I think - no smoke. I made it down the street to the local O'Reillys and they could not tell where the roar was coming from either. They hooked up their analyzer and it read 12.1 (which they said was low).
Battery is only 4 months old Die Hard P4 Platinum and it reads 14.63V - so I think it is fine.
Made it home about 2 miles with the Voltage gage reading about 11.7 all the way (usually is just under 14 and I watch it like a hawk every time I get in the car).
So, any ideas what my problem is? Think I need a new alternator or could this be something else dragging the voltage down that "roars"?
Robert
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
Are you referring to the Idler pulley?
The sound was similar to the sound when you are out of Power Steering fluid and try to turn the wheel, but it checked out to be full when I got home and no steering issues on the way home. Not sure how the steering would affect voltage either unless maybe the power steering pump was somehow seizing up?
I understand the Alternator on the Automatic (like mine) has a Clutch Pulley. Could that be it? Can it even be changed?
The sound was similar to the sound when you are out of Power Steering fluid and try to turn the wheel, but it checked out to be full when I got home and no steering issues on the way home. Not sure how the steering would affect voltage either unless maybe the power steering pump was somehow seizing up?
I understand the Alternator on the Automatic (like mine) has a Clutch Pulley. Could that be it? Can it even be changed?
Last edited by Choreo; Jan 21, 2013 at 10:54 PM.
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,841
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
Are you referring to the Idler pulley?
The sound was similar to the sound when you are out of Power Steering fluid and try to turn the wheel, but it checked out to be full when I got home and no steering issues on the way home. Not sure how the steering would affect voltage either unless maybe the power steering pump was somehow seizing up?
I understand the Alternator on the Automatic (like mine) has a Clutch Pulley. Could that be it? Can it even be changed?
The sound was similar to the sound when you are out of Power Steering fluid and try to turn the wheel, but it checked out to be full when I got home and no steering issues on the way home. Not sure how the steering would affect voltage either unless maybe the power steering pump was somehow seizing up?
I understand the Alternator on the Automatic (like mine) has a Clutch Pulley. Could that be it? Can it even be changed?
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
The roar is louder at idle than when the car is going down the road or accelerating. But the voltage at the gage never improves regardless of speed. Whatever it is, started suddenly without any previous symptoms. Drove a couple miles to the gym and no voltage or roar. Came out 1 hour later, started the car and there it was?
I am not seeing where anyone sells just a replacement clutch?
Last edited by Choreo; Jan 22, 2013 at 12:51 AM.
Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
Could not sleep, so I went ahead and tore into this project tonight...
From what I can tell, with the serpentine belt removed, all the pulleys and idlers except the alternator clutch/pulley appear to be silent if I spin them by hand. When I spin the clutch/pulley on the alternator and stop it with my fingers, it make kind of a raspy sound? I guess that could develop into a "roar" under load a running speed?
I have no frame of reference since i never played with it when it was new to see if it made any sound.
If that is the cause, then since I cannot find any clutch replacements, guess I am looking at a new Alternator again. I see a couple options maybe...
• I see this remanufactured one at O'Reilly with a Lifetime Warranty that says it replaces my Valeo Part Number 10316182 - $169 + $30 core w/FREE Shipping 24 hour delivery
http://www.oreillyauto.com/site/c/de...ord=alternator
Looking online is see a lot of bad reviews on Ultima Alternators - so I guess that is out.
• New OEM from Forum Vendors looks like about $425-$455 + a ton of shipping
This is my only car (DD) - so I need to get something swapped out ASAP.
My alternator...
From what I can tell, with the serpentine belt removed, all the pulleys and idlers except the alternator clutch/pulley appear to be silent if I spin them by hand. When I spin the clutch/pulley on the alternator and stop it with my fingers, it make kind of a raspy sound? I guess that could develop into a "roar" under load a running speed?
I have no frame of reference since i never played with it when it was new to see if it made any sound.
If that is the cause, then since I cannot find any clutch replacements, guess I am looking at a new Alternator again. I see a couple options maybe...
• I see this remanufactured one at O'Reilly with a Lifetime Warranty that says it replaces my Valeo Part Number 10316182 - $169 + $30 core w/FREE Shipping 24 hour delivery
http://www.oreillyauto.com/site/c/de...ord=alternator
Looking online is see a lot of bad reviews on Ultima Alternators - so I guess that is out.
• New OEM from Forum Vendors looks like about $425-$455 + a ton of shipping
This is my only car (DD) - so I need to get something swapped out ASAP.
My alternator...
Last edited by Choreo; Jan 22, 2013 at 02:46 AM.
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,841
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
IN this case ( DD )... I would get anything that has a lifetime warranty.
Rather than an online vendor... dont you have a local Advanced auto, Auto Zone, or Pep Boys??? to swap out the alternator only takes 15 minutes... a lifetime warranty will insure you wont have to pay for another alternator... make sure you keep the receipt somewhere safe, in the event you have a problem.
Good Luck
Bill aka ET
Rather than an online vendor... dont you have a local Advanced auto, Auto Zone, or Pep Boys??? to swap out the alternator only takes 15 minutes... a lifetime warranty will insure you wont have to pay for another alternator... make sure you keep the receipt somewhere safe, in the event you have a problem.
Good Luck
Bill aka ET
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Thread Starter
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
OK... I bit the bullet and installed the Ultima Re-Manufactured Alternator from O'Reilly today.
• The 'roar" went away - so I am guessing it was the clutch/decoupler as we suspected that was causing the sound.
• My voltage on the dash gauge AND the DIC now read 14.3V steady. This is the first time since I have owned the car that I have seen the fabled 14+ Volts! Both my factory Valeo alternators never got me above 13.7 on their best day. I am showing 15.1 Volts at the battery with the car running.
So, I guess this means it WAS the alternator that crapped out - the question is, are these new voltage readings I am getting in the safe zone?
• The 'roar" went away - so I am guessing it was the clutch/decoupler as we suspected that was causing the sound.
• My voltage on the dash gauge AND the DIC now read 14.3V steady. This is the first time since I have owned the car that I have seen the fabled 14+ Volts! Both my factory Valeo alternators never got me above 13.7 on their best day. I am showing 15.1 Volts at the battery with the car running.
So, I guess this means it WAS the alternator that crapped out - the question is, are these new voltage readings I am getting in the safe zone?
Last edited by Choreo; Jan 23, 2013 at 04:14 PM.
Pro
Joined: May 2011
Posts: 580
Likes: 1
From: Chicago Suburb
St. Jude Donor '13
IN this case ( DD )... I would get anything that has a lifetime warranty.
Rather than an online vendor... dont you have a local Advanced auto, Auto Zone, or Pep Boys??? to swap out the alternator only takes 15 minutes... a lifetime warranty will insure you wont have to pay for another alternator... make sure you keep the receipt somewhere safe, in the event you have a problem.
Good Luck
Bill aka ET
Rather than an online vendor... dont you have a local Advanced auto, Auto Zone, or Pep Boys??? to swap out the alternator only takes 15 minutes... a lifetime warranty will insure you wont have to pay for another alternator... make sure you keep the receipt somewhere safe, in the event you have a problem.
Good Luck
Bill aka ET
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,841
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
If I buy anything for my car.. I take a picture of the old part, a picture of the new part, and a picture of the box with the part number, and a picture of the receipt.. I put it in a folder on my computer that says Corvette.. inside that folder I have sub folders like, starter replacement 2011. or water pump replacement 2006... in that way I have documentation. Having a receipt that is 8 years old could very easily be deteriorated to the point that you cant read it.. a copy of that receipt on your computer with be as clear as the day you scanned it. I also have a Book with every receipt for every maintenance item oil and filter receipt, every mod, upgrade, tune, test, inspection, etc.