Winding Alternator
Thread Starter
Racer
Joined: Jan 2008
Posts: 268
Likes: 2
From: Crawfordsville Indiana
Alternator Whine
The alernator on my 98 is singing to me. Battery is fully charged and is on a "Battery Tender" when not in use. The digital gauge says it's putting out 14 amps with no loads applyed. We went for a ride Sunday and we noticed that the alternator was making a loader than normal whining sound. It was a warm day, we had the air on and at a stop the digital gauge was at 13.2 amps. If I put the directional light on or applyed the brake pedal on and off the whining sound followed the beat. The amps would very from say13.2 amps to 13.8. Is the alternator on it's way out?
Last edited by wheelhorse; Oct 12, 2010 at 09:46 PM.
Tech Contributor
Joined: Jan 2007
Posts: 19,425
Likes: 1,146
From: Dyer, IN
The alernator on my 98 is singing to me. Battery is fully charged and is on a "Battery Tender" when not in use. The digital gauge says it's putting out 14 amps with no loads applyed. We went for a ride Sunday and we noticed that the alternator was making a loader than normal winding sound. It was a warm day, we had the air on and at a stop the digital gauge was at 13.2 amps. If I put the directional light on or applyed the brake pedal on and off the winding sound followed the beat. The amps stayed at 13.2 amps. Is the alternator on it's way out?
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
Since you cant drive than take the battery out first and check with autozone or some garage, once its sure that battery is good than take the DMM meter and check voltages before and after loads, both at battery terminals and than connect DMM neg to negative of battery and pos of DMM to terminal (it has rubber boot on) of alternator itself to make sure you getting same voltages.
For loads: turn A/C ON, interior lights ON, and headlights ON, W and W/O loads, alternator should compensate and shows same voltage....for example without loads you read 14.20V and you should read same voltage with LOADS ON or atleast very close to it.
If you alligator clips than put the DMM on window while you read voltage at idle and rev to about 2k rpm.
I suspect your battery is not in top shape or not chraging over 13V's, make sure first battery is good though. However if you getting winding sound than alternator might be suspect too.
For loads: turn A/C ON, interior lights ON, and headlights ON, W and W/O loads, alternator should compensate and shows same voltage....for example without loads you read 14.20V and you should read same voltage with LOADS ON or atleast very close to it.
If you alligator clips than put the DMM on window while you read voltage at idle and rev to about 2k rpm.
I suspect your battery is not in top shape or not chraging over 13V's, make sure first battery is good though. However if you getting winding sound than alternator might be suspect too.
Last edited by sami85L98; Oct 11, 2010 at 08:56 PM.
Pro
Joined: Aug 2010
Posts: 545
Likes: 4
From: Calgary Alberta
This is what my recently departed alternator in my Ford Escape started doing. Analysis of it when it finally failed showed that one diode had a bad solder joint and two hours had overheated and failed. I suspect the whining noise was due to the fact a few of the only half the windings were carrying the load. In short the whining sound was due to overloaded windings. Bad bearings could also be the problem. Bear in mind the alternator has they smallest pulley out of all your accessories therefore it is turning the fastest.
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Thread Starter
Racer
Joined: Jan 2008
Posts: 268
Likes: 2
From: Crawfordsville Indiana
Since you cant drive than take the battery out first and check with autozone or some garage, once its sure that battery is good than take the DMM meter and check voltages before and after loads, both at battery terminals and than connect DMM neg to negative of battery and pos of DMM to terminal (it has rubber boot on) of alternator itself to make sure you getting same voltages.
For loads: turn A/C ON, interior lights ON, and headlights ON, W and W/O loads, alternator should compensate and shows same voltage....for example without loads you read 14.20V and you should read same voltage with LOADS ON or atleast very close to it.
If you alligator clips than put the DMM on window while you read voltage at idle and rev to about 2k rpm.
I suspect your battery is not in top shape or not chraging over 13V's, make sure first battery is good though. However if you getting winding sound than alternator might be suspect too.
For loads: turn A/C ON, interior lights ON, and headlights ON, W and W/O loads, alternator should compensate and shows same voltage....for example without loads you read 14.20V and you should read same voltage with LOADS ON or atleast very close to it.
If you alligator clips than put the DMM on window while you read voltage at idle and rev to about 2k rpm.
I suspect your battery is not in top shape or not chraging over 13V's, make sure first battery is good though. However if you getting winding sound than alternator might be suspect too.
I was also thinking DIODE or maybe the STATOR.
Last edited by wheelhorse; Oct 12, 2010 at 09:44 PM.
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
Alternators have "windings" inside. It's called a stator.
Sometimes alternators "whine".
http://www.crutchfield.com/S-j0NOcZL...ech/kb348.html
Sometimes alternators "whine".
http://www.crutchfield.com/S-j0NOcZL...ech/kb348.html
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
Thread Starter
Racer
Joined: Jan 2008
Posts: 268
Likes: 2
From: Crawfordsville Indiana
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
To find your old threads (for updates), just click on your user name and select from the pull downs.
Did the source of the new VALEO require the core?
To bad there's so few places that rebuild or provide replacement parts for the newer alternators nowadays.
When customers bought brand new instead of rebuilding their parts, we used to call it "planned obsolescence" and that was was in the '60s.
Did the source of the new VALEO require the core?
To bad there's so few places that rebuild or provide replacement parts for the newer alternators nowadays.
When customers bought brand new instead of rebuilding their parts, we used to call it "planned obsolescence" and that was was in the '60s.
Thread Starter
Racer
Joined: Jan 2008
Posts: 268
Likes: 2
From: Crawfordsville Indiana
To find your old threads (for updates), just click on your user name and select from the pull downs.
Did the source of the new VALEO require the core?
To bad there's so few places that rebuild or provide replacement parts for the newer alternators nowadays.
When customers bought brand new instead of rebuilding their parts, we used to call it "planned obsolescence" and that was was in the '60s.
Did the source of the new VALEO require the core?
To bad there's so few places that rebuild or provide replacement parts for the newer alternators nowadays.
When customers bought brand new instead of rebuilding their parts, we used to call it "planned obsolescence" and that was was in the '60s.
I use to take them apart and check the stator, diodes, rectifier bridge, brushes and rotor. Then put a new regulator and bearings in. Good to go. It's hard to get individual parts for this alternator. No core required. I had no choice.
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
Save your parts. Someone might be interested in buying the cases to have them polished or chromed.
For older alternators for US made cars, I've found these two hot rod sources for parts to be outstanding...
http://www.enoscustom.com/
http://madelectrical.com/index.shtml
Mark Harmon runs the second site. He's an electrical guru. Unfortunately, his health hasn't been the best.
For older alternators for US made cars, I've found these two hot rod sources for parts to be outstanding...
http://www.enoscustom.com/
http://madelectrical.com/index.shtml
Mark Harmon runs the second site. He's an electrical guru. Unfortunately, his health hasn't been the best.
Last edited by hotwheels57; Oct 15, 2010 at 01:34 PM.
