Correct Alternator Question 1969 L46

[Keith M.]

So I am in need of a correct alternator for my 69 L46 convertible 4 spd no A/C late October (25th?) 1969 car build date. I have a line on one (option 1)that is a 1100900 dated 9G12 which would seem to be a perfect date code. The JG has that listed amongst the 1969 alternators but asterisked as "1970 alternator is seen sporadically on original 1969 cars from July 1969 to the end of 1969 production". What exactly does that mean? Does it mean to say that the 900 is generally speaking a 1970 part but has been seen on some 69 cars? It would seem to me a July 69 dated part would be too early for a 1970 car? Is the 900 alternator indeed correct for a 1969 car in general. The July date would seem to me to be perfect for a late Oct built car. Are there any performance or technical differences between a 900 and 859?

Alternatively...pun intended...I have another option (option 2) for a 1100859 alternator dated Nov 1968...but that seems way too early for an Oct 69 built car..but possible I guess given the strike and all in 1969.

Lastly, I have also found a 900 alt dated Sept 1969 (option 3)...which could work but a bit closer to car build date.

As for economics...option 1 =$700, option 2 = $750 ..option 3 = $1100..all would be refurb/restored correct.

Seems to me option 1 would be the way to go...pending confirm the part #1100900 is NCRS correct.
Thanks in advance.

[Joe L.]

Re: Correct Alternator Question 1969 L46

So I am in need of a correct alternator for my 69 L46 convertible 4 spd no A/C late October (25th?) 1969 car build date. I have a line on one (option 1)that is a 1100900 dated 9G12 which would seem to be a perfect date code. The JG has that listed amongst the 1969 alternators but asterisked as "1970 alternator is seen sporadically on original 1969 cars from July 1969 to the end of 1969 production". What exactly does that mean? Does it mean to say that the 900 is generally speaking a 1970 part but has been seen on some 69 cars? It would seem to me a July 69 dated part would be too early for a 1970 car? Is the 900 alternator indeed correct for a 1969 car in general. The July date would seem to me to be perfect for a late Oct built car. Are there any performance or technical differences between a 900 and 859?

Alternatively...pun intended...I have another option (option 2) for a 1100859 alternator dated Nov 1968...but that seems way too early for an Oct 69 built car..but possible I guess given the strike and all in 1969.

Lastly, I have also found a 900 alt dated Sept 1969 (option 3)...which could work but a bit closer to car build date.

As for economics...option 1 =$700, option 2 = $750 ..option 3 = $1100..all would be refurb/restored correct.

Seems to me option 1 would be the way to go...pending confirm the part #1100900 is NCRS correct.
Thanks in advance.

Keith------

Option 1 would be your best bet. The 1100900 was used on late 1969 Corvettes. Was it originally used on your car? The only way to know that would be to have the original alternator used on your car and, apparently, you don't have it. Consider this:

1) The 1100900 was a Corvette-only alternator part number;

2) There's no way that an alternator manufactured in July, 1969 was going to be held until 1970 Corvette production started;

3) There is ZERO functional reason that the 1100900 could not have been used on a 1969;

4) Some late 1969 Corvettes have been observed with the 1100900 alternator

What more would you need to convince you that this alternator would be correct for your car? However, make sure that the front and rear case halves are of the correct configuration for an early build 1100900 alternator

[Terry M.]

Re: Correct Alternator Question 1969 L46

Keith

Let me try to explain the situation owners, like you, of "late" 1969s are faced with.

Ordinarily Corvette model year production ran from August to July. However, in 1969 model year Corvette (and Camaro) production ran from August 1968 to December 1969. All other Chevrolet models began 1970 model year production in August of 1969, while Corvette (and Camaro) continued producing 1969 Models. Thus all those supplying divisions of GM produced both 1969 and 1970 parts for those 5 months of overlapping model year production.

In some cases the 1969 and 1970 parts were no different, and in other cases the configuration was that of 1969, and in other cases the configuration was that of 1970.

To cite just two examples for 1969 model year Corvettes built between August 1969 and December 1969:
The engine stamping codes remained the two character format of 1969
The rear axel stamped codes began the three character code of 1970

It appears so far from our research that alternator stamp IDs were a mixed bag, probably for the functional reason Joe L cited above. Thus the note regarding 1970 alternators in the 1968/69 TIM&JG.

I hope this helps you and other owners of the later 1969 Corvettes better understand the unique build situations that resulted from Chevrolet producing 1969 and 1970 models at the same time.

[Keith M.]

Re: Correct Alternator Question 1969 L46

Keith------

Option 1 would be your best bet. The 1100900 was used on late 1969 Corvettes. Was it originally used on your car? The only way to know that would be to have the original alternator used on your car and, apparently, you don't have it. Consider this:

1) The 1100900 was a Corvette-only alternator part number;

2) There's no way that an alternator manufactured in July, 1969 was going to be held until 1970 Corvette production started;

3) There is ZERO functional reason that the 1100900 could not have been used on a 1969;

4) Some late 1969 Corvettes have been observed with the 1100900 alternator

What more would you need to convince you that this alternator would be correct for your car? However, make sure that the front and rear case halves are of the correct configuration for an early build 1100900 alternator

Joe,
Thank you for the response. Part of my reason for wanting to validate my understanding was that the wording in the JG could, I believe, be made clearer to those like myself who are not yet as knowledgeable as we hope to be one day. Allow me to elaborate. The listing of alternators on p146 includes the 1100900 which has a ** footnote that applies only to that alternator number. The associated footnote states "** 1970 alternator is seen sporadically on original 1969 cars from July 1969 to the end of 1969 production." So what I NOW glean from this footnote is that the 900 alternator is by original intent NOT a 1969 MY alternator, but has been observed "sporadically" in survivor vehicles...as stated in the footnote...and for reasons further elaborated by Terry in his post. A different interpretation...however illogical...I had initially...was that the footnote was referring to 1100900 alternators with 1970 date stamps. I mean...to truly be a "1970 alternator" that would have to be an alternator MADE in 1970, no? But certainly any alternator could not have a date code that is beyond the car build date...so given all this I think I am good with the July 1969 dated 900 alternator.

Perhaps the footnote could remove any ambiguity by stating "**the 1100900 was primarily a 1970 MY part but has been seen sporadically on original 1969 cars...etc." ..or even "THIS model year 1970 alternator....."

Has anyone ever documented the 1969 strike and other circumstances that happened to make that such an usual year? I found Terry's elaboration very interesting.

Thanks to all for the continued education!

[Joe L.]

Re: Correct Alternator Question 1969 L46

Joe,
Thank you for the response. Part of my reason for wanting to validate my understanding was that the wording in the JG could, I believe, be made clearer to those like myself who are not yet as knowledgeable as we hope to be one day. Allow me to elaborate. The listing of alternators on p146 includes the 1100900 which has a ** footnote that applies only to that alternator number. The associated footnote states "** 1970 alternator is seen sporadically on original 1969 cars from July 1969 to the end of 1969 production." So what I NOW glean from this footnote is that the 900 alternator is by original intent NOT a 1969 MY alternator, but has been observed "sporadically" in survivor vehicles...as stated in the footnote...and for reasons further elaborated by Terry in his post. A different interpretation...however illogical...I had initially...was that the footnote was referring to 1100900 alternators with 1970 date stamps. I mean...to truly be a "1970 alternator" that would have to be an alternator MADE in 1970, no? But certainly any alternator could not have a date code that is beyond the car build date...so given all this I think I am good with the July 1969 dated 900 alternator.

Perhaps the footnote could remove any ambiguity by stating "**the 1100900 was primarily a 1970 MY part but has been seen sporadically on original 1969 cars...etc." ..or even "THIS model year 1970 alternator....."

Has anyone ever documented the 1969 strike and other circumstances that happened to make that such an usual year? I found Terry's elaboration very interesting.

Thanks to all for the continued education!

Keith------


The 1100900 is generally considered to be a 1970 MODEL YEAR alternator. However, alternator part numbers often transcend specific model year application. For example, alternator GM #1100693 was used from 1965 thru 1968. The year model that any particular 1100693 was originally installed on is determined by the stamped date, not the alternator part number. The GM #1100900 is the same in the sense that it could have been installed on late 1969's as well as 1970's. As I stated before, there is absolutely no functional reason that the 1100900 could not have been installed on a 1969. The fact that the alternator was manufactured in July, 1969 virtually guarantees that it was installed on some 1969 Corvette. In that it was installed on some 1969 Corvette, that Corvette could have been your Corvette. Was it your Corvette? No one will ever know, for sure.

[Gary B.]

Re: Correct Alternator Question 1969 L46

68-69 TIM&JG has been updated to read:

This model year 1970 alternator (1100900) is seen sporadically on original 1969 cars from July 1969 to the end of 1969 production (but correctly dated for the car).

Gary B

[Keith M.]

Re: Correct Alternator Question 1969 L46

Keith------

Option 1 would be your best bet. The 1100900 was used on late 1969 Corvettes. Was it originally used on your car? The only way to know that would be to have the original alternator used on your car and, apparently, you don't have it. Consider this:

1) The 1100900 was a Corvette-only alternator part number;

2) There's no way that an alternator manufactured in July, 1969 was going to be held until 1970 Corvette production started;

3) There is ZERO functional reason that the 1100900 could not have been used on a 1969;

4) Some late 1969 Corvettes have been observed with the 1100900 alternator

What more would you need to convince you that this alternator would be correct for your car? However, make sure that the front and rear case halves are of the correct configuration for an early build 1100900 alternator

This doesn't change the main points nor the game plan here...but technically...#2 above would not seem to be the case if MY1970 builds started in August of 1969...but again...1969 was an atypical production timing year....and I myself do not know for fact when the 1970 corvettes commenced building that particular year but understand that in a typical year August would begin production of models for the following calendare year.
Keith

[Terry M.]

Re: Correct Alternator Question 1969 L46

This doesn't change the main points nor the game plan here...but technically...#2 above would not seem to be the case if MY1970 builds started in August of 1969...but again...1969 was an atypical production timing year....and I myself do not know for fact when the 1970 corvettes commenced building that particular year but understand that in a typical year August would begin production of models for the following calendare year.
Keith

Model Year 1970 REGULAR Corvette production began on January 5, 1970. Now you know.

[Keith M.]

Re: Correct Alternator Question 1969 L46

Model Year 1970 REGULAR Corvette production began on January 5, 1970. Now you know.

Thank you. So if I understand correctly....and per your other post...typical production years would end in July...which in 1969 it did for non-Corvette/Camaro GM models...but the Vette/Camaro 1969MY continued running through December and switched to 1970MY builds in Jan 1970. So as you said...that period of Aug to Dec 69 GM is pumping out 69 vettes (and Camaros) and 1970MY "everything else"...thus the parts and date code challenges of an Oct 25 1969 build car like mine. But I gotta stick with it ...being as it was within 5 days of my 8th birthday!! So does this make my car worth tens of thousands of dollars more as it is rare/unusual for a car to be built in October of it's own model year??? ;-)

[Terry M.]

Re: Correct Alternator Question 1969 L46

Thank you. So if I understand correctly....and per your other post...typical production years would end in July...which in 1969 it did for non-Corvette/Camaro GM models...but the Vette/Camaro 1969MY continued running through December and switched to 1970MY builds in Jan 1970. So as you said...that period of Aug to Dec 69 GM is pumping out 69 vettes (and Camaros) and 1970MY "everything else"...thus the parts and date code challenges of an Oct 25 1969 build car like mine. But I gotta stick with it ...being as it was within 5 days of my 8th birthday!! So does this make my car worth tens of thousands of dollars more as it is rare/unusual for a car to be built in October of it's own model year??? ;-)

You have the issue of 1969 and 1970 model year production correct.

I would have to look up the numbers for Corvette production in those five months, but my guess is tens of thousands of Corvettes were built during that time. I see no added value to a car produced during that time just because of its production date. On the other hand, having a car built that close to your birthday should add value to you. Enjoy it.

[Richard K.]

Re: Correct Alternator Question 1969 L46

For what it's worth, my late-build, November 25, 1969 Corvette, that I've owned since Feb '75, has a 900 alternator. I strongly believe that it is original to the car. The alternator has a build date of 9L6, November 6th of 1969 (I believe no "I" was used in dating). So, only 19 days elapsed from the day the alternator was built until it was installed on the engine.