68 L79 Alternator and Voltage Regulator

[Richard D.]

Believe that my charging system is not functioning properly.

Noticed that after running for 45 mins to an hour, that the battery takes about that long to get back to a full charge on a 6 amp Sears charger. Seems like it should be near fully charged after running that long. I always recharge the battery, so when I start off, I know it has a full charge.

It will sit a full week without losing any charge. I have a cut-off switch on the battery that I use when the car's not in use.

I did put in a new (repro) amp guage over the winter, and that seems to be working OK. The needle though hardly moves off 0 (zero) when running, but will dip slightly below 0 when I pull the lights on. Car also has a new engine wiring harness, dash harness, ignition switch, headlight switch, and turn signal harness installed this winter, and all other things seem to work fine.

Anyway, going to start testing the alternator, etc, this coming weekend, and was wondering what to get if I have to:

1. Replace the alternator? Original part 1100693, 37 amp rated. Can I put a higher output alt. in the car without changing anything else, or causing harm to anything? Tried GM Parts Direct, but it had no alternators listed, just replacement parts for them.

2. Voltage Regulator (or Regulator Assm. - Voltage, per the AIM) original part #1119515. Where can I get one that you experts out there might recommend?

Tried GM Parts Direct for both, but they had nothing.

It currently has and Eichlin VR in in now, and a chrome Alt. that came with the car when I bought it.

Any other ideas on what to troubleshoot would be appreciated also. I will check out all wiring connections and look for anything that looks "cooked" when I start my investigations this coming weekend.

Thanks, as always, for any advice.

Regards,

Rich

[Dave F.]

Re: 68 L79 Alternator and Voltage Regulator

Rich,

I bought the 37 amp alt. plus matching voltage regulator from Sweeney Chevrolet (Cincinnati) earlier this spring

[Dave F.]

Re: 68 L79 Alternator and Voltage Regulator

Rich,

I bought the 37 amp alt. plus matching voltage regulator from Sweeney Chevrolet (Cincinnati) earlier this spring

[Joe L.]

Re: 68 L79 Alternator and Voltage Regulator

Rich-----

Unless you've added significant electrical draw, a 37 amp alternator should be adequate for your application. If you want a correct alternator, you're going to have to get one from a source like John Pirkle. He can provide you with an up-to-spec functioning, originally numbered and dated alternator. It won't be cheap, though. Also, if you wish, he could upgrade the unit to a higher amperage by changing the stator. This can be done without changing the external appearance of the alternator, but John will probably advise you that it's unnecessary unless you've added significant electrical demand. If your current alternator will not properly restore battery charge, I would expect that the problem is a functional deficiency rather than just a basic lack of capacity due to its amp rating.

If you wish to obtain a fully rebuilt, higher amperage unit irrespective of "numbers" and "dates", you can obtain a 52 amp unit from GM under GM #12321162 or Delco #321-161. This unit should be, generally, the correct configuration for you application except for "numbers".

Regulator GM #1119515 is long-since GM-discontinued. You can obtain a fully rebuilt one, correct in every detail, from John Pirkle and others. It won't be cheap, either. If you don't care about fine detail, "numbers, and "dates", you can obtain a brand new unit from GM under GM #1119519. This unit will have a "generic" style cover and will differ in other fine details from the original. However, it will be BRAND NEW, fully functional, and correct in GENERAL configuration. These units are NOT manufactured by Delco-Remy or, even DELPHI. In today's world, Delco-Remy and DELPHI are GM spin-off companies and, as far as I know, neither one manufactures electro-mechanical voltage regulators any more. AC-Delco, under which brand name the 1119519 regulator is sold, is a GM parts MARKETING organization and NOT a parts MANUFACTURING operation . As far as I know, AC-Delco does not manufacture a single part. So, this regulator is made by some other parts manufacturing "entity". Nevertheless, I feel pretty confident that it will be a quality unit.

By the way, although not the case with alternators, most "original GM parts" for Corvettes were not made by a GM parts manufacturing operation. For the most part, GM in-house parts manufacturing operations of old were geared up for high volume parts manufacture. Low volume parts were generally "outsourced", both then and now. Corvette-specific parts always were and remain low volume parts by definition.

A great example of this which is really a "crystal clear" lesson in this policy is 4 speed transmissions. During the 57-63 period, the demand for 4 speed transmissions was relatively low. So, GM out-sourced them to Borg Warner. In the early 60s demand started to increase dramatically. So, GM brought them in-house by purchasing a Borg-Warner manufacturing operation in Muncie, IN and designing/building it's own 4 speed transmission. When demand took another leap, a second design and manufacturing facility was added in Saginaw, MI. However, in the mid 70s demand started to drop significantly. So, the Muncie was gone after 1974, the Saginaw "soldiered on" for a few more years, and the main 4 speed business was outsourced to Borg-Warner again.

[Joe L.]

Re: 68 L79 Alternator and Voltage Regulator

Rich-----

Unless you've added significant electrical draw, a 37 amp alternator should be adequate for your application. If you want a correct alternator, you're going to have to get one from a source like John Pirkle. He can provide you with an up-to-spec functioning, originally numbered and dated alternator. It won't be cheap, though. Also, if you wish, he could upgrade the unit to a higher amperage by changing the stator. This can be done without changing the external appearance of the alternator, but John will probably advise you that it's unnecessary unless you've added significant electrical demand. If your current alternator will not properly restore battery charge, I would expect that the problem is a functional deficiency rather than just a basic lack of capacity due to its amp rating.

If you wish to obtain a fully rebuilt, higher amperage unit irrespective of "numbers" and "dates", you can obtain a 52 amp unit from GM under GM #12321162 or Delco #321-161. This unit should be, generally, the correct configuration for you application except for "numbers".

Regulator GM #1119515 is long-since GM-discontinued. You can obtain a fully rebuilt one, correct in every detail, from John Pirkle and others. It won't be cheap, either. If you don't care about fine detail, "numbers, and "dates", you can obtain a brand new unit from GM under GM #1119519. This unit will have a "generic" style cover and will differ in other fine details from the original. However, it will be BRAND NEW, fully functional, and correct in GENERAL configuration. These units are NOT manufactured by Delco-Remy or, even DELPHI. In today's world, Delco-Remy and DELPHI are GM spin-off companies and, as far as I know, neither one manufactures electro-mechanical voltage regulators any more. AC-Delco, under which brand name the 1119519 regulator is sold, is a GM parts MARKETING organization and NOT a parts MANUFACTURING operation . As far as I know, AC-Delco does not manufacture a single part. So, this regulator is made by some other parts manufacturing "entity". Nevertheless, I feel pretty confident that it will be a quality unit.

By the way, although not the case with alternators, most "original GM parts" for Corvettes were not made by a GM parts manufacturing operation. For the most part, GM in-house parts manufacturing operations of old were geared up for high volume parts manufacture. Low volume parts were generally "outsourced", both then and now. Corvette-specific parts always were and remain low volume parts by definition.

A great example of this which is really a "crystal clear" lesson in this policy is 4 speed transmissions. During the 57-63 period, the demand for 4 speed transmissions was relatively low. So, GM out-sourced them to Borg Warner. In the early 60s demand started to increase dramatically. So, GM brought them in-house by purchasing a Borg-Warner manufacturing operation in Muncie, IN and designing/building it's own 4 speed transmission. When demand took another leap, a second design and manufacturing facility was added in Saginaw, MI. However, in the mid 70s demand started to drop significantly. So, the Muncie was gone after 1974, the Saginaw "soldiered on" for a few more years, and the main 4 speed business was outsourced to Borg-Warner again.

[Jim T.]

Re: 68 L79 Alternator and Voltage Regulator

I made the mistake of trading in my original 37 amp 1100693 68 alternator for one off the shelf at Auto Zone many years ago (about 1978) before I learned about retaining original stuff. Anyway, the replacement alternator was a 42 amp unit and is still working today. Advance Auto sells Delco rebuilt alternators. You could take the chrome unit to a electrcal shop and let them check it out, you may just want it repaired

[Jim T.]

Re: 68 L79 Alternator and Voltage Regulator

I made the mistake of trading in my original 37 amp 1100693 68 alternator for one off the shelf at Auto Zone many years ago (about 1978) before I learned about retaining original stuff. Anyway, the replacement alternator was a 42 amp unit and is still working today. Advance Auto sells Delco rebuilt alternators. You could take the chrome unit to a electrcal shop and let them check it out, you may just want it repaired

[Richard D.]

Re: 68 L79 Alternator and Voltage Regulator

Joe, as usual, thanks for the info.

Not sure if I'm going to go for the fully correct (numbers and dates thing) right now, so the GM replacement numbers you have furnished may be the way I go as I would feel more confidence in them, versus cheaper Auto Store type replacements.

Since I have not redone the car with any other high draw electrical parts or components, the 37 should work OK for me, if indeed I need to replace the current alt, although I would like to get a non-chrome alt. on the car.

Thanks again for the info. on this, and the backround info. too.

Regards,

Rich

[Richard D.]

Re: 68 L79 Alternator and Voltage Regulator

Joe, as usual, thanks for the info.

Not sure if I'm going to go for the fully correct (numbers and dates thing) right now, so the GM replacement numbers you have furnished may be the way I go as I would feel more confidence in them, versus cheaper Auto Store type replacements.

Since I have not redone the car with any other high draw electrical parts or components, the 37 should work OK for me, if indeed I need to replace the current alt, although I would like to get a non-chrome alt. on the car.

Thanks again for the info. on this, and the backround info. too.

Regards,

Rich

[Richard D.]

Re: 68 L79 Alternator and Voltage Regulator

Thanks Dave.

I'll try my local dealer and see if he can do a parts search for me if I need the parts.

Maybe Sweeney still has some if I strike out with my guys here.

By the way, do you remember how much the parts went for?

Thanks again,

Rich

[Richard D.]

Re: 68 L79 Alternator and Voltage Regulator

Thanks Dave.

I'll try my local dealer and see if he can do a parts search for me if I need the parts.

Maybe Sweeney still has some if I strike out with my guys here.

By the way, do you remember how much the parts went for?

Thanks again,

Rich

[John Pickens]

Re: 68 L79 Alternator and Voltage Regulator

A reliable starter/alternator rebuilder/repair shop can tell you the functional
status of your unit in about ten minutes. I had mine checked and repaired(for
my 65 327/350 with AC) for about twenty bucks. Another option is to purchase a
ten dollar replacement regulator at Advance and see if the situation improves. My experience with both the mechanical and solid state units(same price) has been good reliability and just maybe a cheap fix as well. And if that fixes the problem you can then investigate a numbered rebuilt replacement if need be.

[John Pickens]

Re: 68 L79 Alternator and Voltage Regulator

A reliable starter/alternator rebuilder/repair shop can tell you the functional
status of your unit in about ten minutes. I had mine checked and repaired(for
my 65 327/350 with AC) for about twenty bucks. Another option is to purchase a
ten dollar replacement regulator at Advance and see if the situation improves. My experience with both the mechanical and solid state units(same price) has been good reliability and just maybe a cheap fix as well. And if that fixes the problem you can then investigate a numbered rebuilt replacement if need be.

[Joe L.]

Re: 68 L79 Alternator and Voltage Regulator

Rich-----

I don't think that Delco has the DN-series alternators (i.e. Corvette pre-1969) available anymore in 37 or 42 amp with the Corvette "clock" configuration. Other rebuilders might, though. The Delco/GM unit I described is a 52 amp. Using it will not hurt anything even though you likley don't need that output amperage. If you were going with an ORIGINAL, restored alternator from someone like John Pirkle, you wouldn't need to have it upgraded from original spec, though.

[Joe L.]

Re: 68 L79 Alternator and Voltage Regulator

Rich-----

I don't think that Delco has the DN-series alternators (i.e. Corvette pre-1969) available anymore in 37 or 42 amp with the Corvette "clock" configuration. Other rebuilders might, though. The Delco/GM unit I described is a 52 amp. Using it will not hurt anything even though you likley don't need that output amperage. If you were going with an ORIGINAL, restored alternator from someone like John Pirkle, you wouldn't need to have it upgraded from original spec, though.