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Old Mar 12, 2014 | 10:36 AM
  #1  
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Default Bad alternator

I'm pretty sure I have a bad alternator. Even as I drive, the volts read at 11.5ish. Thats not enough to crank over the car in my experience. I think Ive been fine because I have a deep cycle battery, but that wont last long I'm sure.

So should I have the alternator tested? Do places like Autozone still do that?

And also, does anyone know where the cheapest place to get a replacement is? Im seeing this alternator for a whopping 400-500 on several sites. Why is this 300+ more $$$ than other cars?
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Old Mar 12, 2014 | 11:04 AM
  #2  
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I took mine to Advanced to have it tested and they said that it was fine. I noticed that on the test sheet, there was no test for the L-terminal. They were wrong.

Check out these posts. Hope they help you

The cheapest way to fix it is to rebuild your old one.

Wholesale Alternator & Starter Parts
6160 Skyline Ct
Spring Hill, Florida 24606
353-688-3206
www.aspwholesale.com
$41.08, Part Number M526, regulator/Brush Holder Assy, Valeo IR/IF Alternators 12 Volt, B-Circuit, S-FR-L-D terminals



http://forums.corvetteforum.com/c5-g...rnator-c5.html

http://forums.corvetteforum.com/c5-t...-pls-help.html

Last edited by Bill McCassey; Mar 12, 2014 at 11:08 AM.
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Old Mar 12, 2014 | 12:52 PM
  #3  
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From: Chicago Suburb
St. Jude Donor '13
Default Alternator

Originally Posted by Bill McCassey
I took mine to Advanced to have it tested and they said that it was fine. I noticed that on the test sheet, there was no test for the L-terminal. They were wrong.

Check out these posts. Hope they help you

The cheapest way to fix it is to rebuild your old one.

Wholesale Alternator & Starter Parts
6160 Skyline Ct
Spring Hill, Florida 24606
353-688-3206
www.aspwholesale.com
$41.08, Part Number M526, regulator/Brush Holder Assy, Valeo IR/IF Alternators 12 Volt, B-Circuit, S-FR-L-D terminals



http://forums.corvetteforum.com/c5-g...rnator-c5.html

http://forums.corvetteforum.com/c5-t...-pls-help.html
Agree. Your best bet is to replace with an OEM unit or re-build your original. C5's are notoriously picky when it comes to alternators. BTW, +$300 is due to Corvette Tax because we are all wealthy. Also, don't trust your DIC to read volts; use a meter at the battery.
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Old Mar 12, 2014 | 07:19 PM
  #4  
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Thanks guys, I'll look into a re-manufactured unit.
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Old Mar 13, 2014 | 02:00 AM
  #5  
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Default

Originally Posted by NukeC5
I'm pretty sure I have a bad alternator. Even as I drive, the volts read at 11.5ish. Thats not enough to crank over the car in my experience. I think Ive been fine because I have a deep cycle battery, but that wont last long I'm sure.

So should I have the alternator tested? Do places like Autozone still do that?

And also, does anyone know where the cheapest place to get a replacement is? Im seeing this alternator for a whopping 400-500 on several sites. Why is this 300+ more $$$ than other cars?
Hey Nuke, I was having the same issues about 2 weeks ago. My 12yr old alternator was on the way out. Would start out at 13.3v and be at 11.0v within minutes. I got a new alternator at Autozone for the warranty and also because it turned out to be an oem Valero alternator. It comes in a Duralast box but it was Valero. I was surprised myself. They only cost about $150-160 depending on what pulley you need. Autos have a decoupler pulley. Mine has been trouble free so far.
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Old Mar 13, 2014 | 10:59 AM
  #6  
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Quicksilver Vert 01
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From: Somers, CT and Clermont, FL
St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16
Default

Originally Posted by C5Natie
I got a new alternator at Autozone for the warranty and also because it turned out to be an oem Valero alternator. It comes in a Duralast box but it was Valero. I was surprised myself. They only cost about $150-160 depending on what pulley you need. Autos have a decoupler pulley. Mine has been trouble free so far.
Not a bad price for an OEM alternator, and with a lifetime warranty to boot!
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Old Mar 13, 2014 | 01:05 PM
  #7  
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I'll definitely take a look at it. Thanks Natie
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Old Mar 31, 2014 | 09:12 PM
  #8  
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Well unfortunately after replacing the alternator to no avail, it turned out to be a loose bolt on the positive line to the starter solenoid. This was causing a no charge situation. Further unfortunate is the fact that the bolt became welded in place because it was backed out against the LT headers. New starter is going in now. And even more unfortunate is the fact that the passengers side header needs removed to get at the starter! So I will have replaced the battery, alternator, and starter all to fix this issue . Oh well, at least I have all new of the big three electrical components. But the labor on the starter swap will be a hard hit due to the headers
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Old Mar 31, 2014 | 09:24 PM
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Default

Originally Posted by NukeC5
Well unfortunately after replacing the alternator to no avail, it turned out to be a loose bolt on the positive line to the starter solenoid. This was causing a no charge situation. Further unfortunate is the fact that the bolt became welded in place because it was backed out against the LT headers. New starter is going in now. And even more unfortunate is the fact that the passengers side header needs removed to get at the starter! So I will have replaced the battery, alternator, and starter all to fix this issue . Oh well, at least I have all new of the big three electrical components. But the labor on the starter swap will be a hard hit due to the headers
That's unfortunate, changing the starter when you have longtubes is such a pain in the behind. I installed header studs last time I removed the headers (to replace starter) to make header removal easier in the future
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