Alternator identification needed ..help!

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Oct 5, 2010 | 09:50 PM

Iggycat2009

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Racer

Joined: Sep 2009

Posts: 429

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From: Oak Ridge NJ

Alternator identification needed ..help!

I have the two alternators and trying to save some $$ by installing #2 which is freshly rebuilt, but appears the amp rating is lower than the one installed and not sure it'll work. The housings and electrical connections are almost identical on both. I'm looking to find out what year each alternator is. Any help would be appreciated.

1) this one is already installed in my 1976 C3;

1105565 78A
6F04 12VNEG

2) This one is rebuilt and ready for installation but not sure it'll work on my 76 C3, the Amp rating is lower;

1100946 55A
3H17 12VNEG

Thanks

Mike

Oct 6, 2010 | 05:07 PM

MelWff

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I dont think you can go by what is stamped from the factory on a rebuilt alternator. The rebuilder may have changed the rating. They both should be bench tested to see what you really have.

Oct 6, 2010 | 07:23 PM

Mike Ward

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Joined: Jul 2001

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Either of those alternators will work on your car if you don't have a/c. Neither is from a Corvette, the first one was built in 1973, the second in 1976.

Oct 7, 2010 | 11:58 AM

jasselmeier

Intermediate

Joined: Apr 2007

Posts: 35

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From: Columbia, IL

How is the coding deciphered? Is this in Corvette by the Numbers?Thanks - Joe

Oct 9, 2010 | 12:16 PM

Iggycat2009

Thread Starter

Racer

Joined: Sep 2009

Posts: 429

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From: Oak Ridge NJ

What makes an alternator significant to a Corvette? If these are both GM alternators, what is the difference?

Mike

Oct 9, 2010 | 01:33 PM

toddalin

Le Mans Master

Joined: Oct 2000

Posts: 8,897

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From: Santa Ana CA

Quote:

Originally Posted by Iggycat2009

What makes an alternator significant to a Corvette? If these are both GM alternators, what is the difference?

Mike

1) Part number stamped on the case, and sometimes clocking of the case.

2) Originality = resale and/or collector value.

Oct 9, 2010 | 01:38 PM

toddalin

Le Mans Master

Joined: Oct 2000

Posts: 8,897

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From: Santa Ana CA

Quote:

Originally Posted by jasselmeier

How is the coding deciphered? Is this in Corvette by the Numbers?Thanks - Joe

1105565 78A
6F04 12VNEG

1105565 is the GM part number

78A = 78 amps

6 = 1976

F = 6th month

04 = 4th day of the month

12VNEG = 12 volt negative ground