1986 Alternator

[Robert G.]

Looking for help on a 1986 alternator. I am the second owner of a 900 orignal mile June-86' built convertible. I am going to have my car judged in a few months and I was going over the manuals and literature. According to all the data I found the alternator should have a part number and date stamp. I have done everything but remove the alternator trying to verify this since it is "judgeable". The only thing I found aside from the raised as-cast Delco Remy on the rear side was an ink stamp on the front passsagner-side face "MH". Just below the "MH" are what appear to be "dot pins" but they are not legible. Based on what I know about the car's history and the condition of the alternator, bolts, bracket, interface etc this part is original. Any help greatly appreciated.

[Don G.]

Re: 1986 Alternator

The dot matrix next to the broadcast code contains the following information:

Part No. 1105678 ( on my car)

Date Code:
4 digits
first digit month
second & third digit day of month
fourth digit last digit of year Example (my car) 3236 March 23, 1986

105 A
12V NEG

If you remove your alternator, you can probably read the matrix with magification.

If you send me a private message with your email address, I can send you a picture,

[Robert G.]

Re: 1986 Alternator

Don - Thanks for the reply, this is exactly what I needed. The dot matrix is really hard to read with a mirror but it is there and it is correct. Robert

[Peter M.]

Re: 1986 Alternator

Here are photos of my OEM alternator on my 86 roadster which should help you ID the proper location and configuration of the original alternator setup.

FWIW,

P.

[Gregory G.]

Re: 1986 Alternator

On my 86 alternator there are numbers stamped on the inside flange of the pulley 964 and opposite of that is an M. Can anyone discern these numbers and its letter?
Also there are yellow paint daubs on the pulley center bolt and one of the rear housing bolts and a spread of yellow paint on the rear section of the alternator.
No pin dot matrix on the flange but a black stamp 7890 where the matrix would be located.
The electrical connection has 4 prongs one thicker and taller than the other three?
It is stamped in the rear Delco Remy with a a number 64 on the opposite rear section on the rear side.
Any incite to this alternator would be appreciated.

Greg

[Peter M.]

Re: 1986 Alternator

On my 86 alternator there are numbers stamped on the inside flange of the pulley 964 and opposite of that is an M. Can anyone discern these numbers and its letter?
Also there are yellow paint daubs on the pulley center bolt and one of the rear housing bolts and a spread of yellow paint on the rear section of the alternator.
No pin dot matrix on the flange but a black stamp 7890 where the matrix would be located.
The electrical connection has 4 prongs one thicker and taller than the other three?
It is stamped in the rear Delco Remy with a a number 64 on the opposite rear section on the rear side.
Any incite to this alternator would be appreciated.

Greg

Take a photo of the underside of your alternator where the part number and date codes are stamped and post it here so we can take a look at it. The date code you list may be from a 1990 service replacement alternator.

[Gregory G.]

Re: 1986 Alternator

Here is one photo with the numbers on the pulley 964 and M opposite end.
20120615_112740.jpg

[Gregory G.]

Re: 1986 Alternator

I have another alternator that came off of an '86 the dot matrix part # 1101601Y 105A, date code 531J2 12v NEG.
The J is hard to make out even after I shaded it in pencil.
The pulley is unpainted steel finish.
With a daub of paint yellow on the locking nut.
The fan blades are black.
Delco Remy is embossed in the rear.
There are several numbers stamped in the rear 4 windows below Delco Remy.
Do not know what they represent?
The large mounting side where dot matrix number is located the hole is not threaded.
Is this another applicable part number for '86 corvette or applicable for other vehicles as well?

[Peter M.]

Re: 1986 Alternator

No, I don't think this alternator is from an 86 Corvette. Perhaps Tom Hendricks can tell you what MY GM vehicle it came from.

[John A.]

Re: 1986 Alternator

One more alternater ID question. The alternator that came with my 86 has this info stamped into it; 1st line - 1101264 (264 is stamped by a hand stamp over the last three dot matrix numbers) 105A (the 5 is hand stamped over the last dot matrix number wich appears to be a zero) 2nd line - 11036A 12vneg. The hand stamped numbers are slightly larger than the dot matrix numbers in height and are not alligned perfectly over the original numbers. My question is if this could have been the original alternator that came with my 1986 Coupe? It was built in March of 1986 and I bought it when it had 24000 miles on it in 1994. I have no reason to beleive it was replaced, but anything is possible. There are no signs of a sticky label being placed over the numbers as would be the case with most rebuilt alternators. My 86 is very, very original and untampered with, but I do not know the history from the previous owner. The date code line has an A at the end and I'm not sure what that means, is it date coded November 3, 1986, shift A? That would make it too late for my 1986!

[Peter M.]

Re: 1986 Alternator

1986 was the first year of use for the CS130 alternator on GM cars. 1993 was the last (AFAIK) and it was replaced by the similar, but much more reliable, internal-fan CS130D in 1994. So 1986 Corvettes have the first year of this not-very-good alternator.

The CS130 alternator is notoriously unreliable. They do not last, frequently fail, and most likely have been changed by now. I judged a 1988 C4 that had 7, yes seven miles on it that had a 1990 alternator date. The 84-89 NTL has replaced the alternator on his 60K-ish mile 86 coupe at least 5 times. I changed the last one for him on the floor of the National Convention in San Diego so he could drive it home to NorCal. I know of two OO CS130 cars that have retained their original cases, even though the guts have been worked on. But these Original Owners went the extra steps to retain the original cases (like most NCRS OO's will).

Yours is a CS130, the date doesn't fit the car, and has non-typical markings. This C4 Judge would be very skeptical of it being original to the car without additional visual input such as colors, finishes, markings on fasteners, etc.

I agree with your comments, Dave. The alternator on my 86 Vette has been changed numerous times as these original CS130 alternators just do not last. I still have the original alternator which John Perkle rebuilt for me in 2008. This is the alternator that you judged at the 2010 Charlotte National meet. Just last week, the original rebuilt alternator FAILED yet again with just 1800 miles on it.

At the expense of hijacking this thread, can the internals of the improved 1993 alternators be configured into the original CS130 alternators, or do we just resign ourselves to the constant rebuilding of these sub-standard CS130 alternators?

[Joe L.]

Re: 1986 Alternator

One more alternater ID question. The alternator that came with my 86 has this info stamped into it; 1st line - 1101264 (264 is stamped by a hand stamp over the last three dot matrix numbers) 105A (the 5 is hand stamped over the last dot matrix number wich appears to be a zero) 2nd line - 11036A 12vneg. The hand stamped numbers are slightly larger than the dot matrix numbers in height and are not alligned perfectly over the original numbers. My question is if this could have been the original alternator that came with my 1986 Coupe? It was built in March of 1986 and I bought it when it had 24000 miles on it in 1994. I have no reason to beleive it was replaced, but anything is possible. There are no signs of a sticky label being placed over the numbers as would be the case with most rebuilt alternators. My 86 is very, very original and untampered with, but I do not know the history from the previous owner. The date code line has an A at the end and I'm not sure what that means, is it date coded November 3, 1986, shift A? That would make it too late for my 1986!

John-----


The GM #1101264 alternator was first used for the 1988 model year and then used through 1990. It was used on 1988-90 Corvettes as well as 89-90 police cars. It may have been used on other GM carlines, but I can't confirm that.

[Joe L.]

Re: 1986 Alternator

I agree with your comments, Dave. The alternator on my 86 Vette has been changed numerous times as these original CS130 alternators just do not last. I still have the original alternator which John Perkle rebuilt for me in 2008. This is the alternator that you judged at the 2010 Charlotte National meet. Just last week, the original rebuilt alternator FAILED yet again with just 1800 miles on it.

At the expense of hijacking this thread, can the internals of the improved 1993 alternators be configured into the original CS130 alternators, or do we just resign ourselves to the constant rebuilding of these sub-standard CS130 alternators?

Peter-----

The CS-130 alternator was used on Corvettes from 1986 through 1991, except ZR1. 1990-95 Corvettes with ZR1 used the CS-144 alternator. The CS-144 was also used for all 1992-96 Corvettes with LT1 or LT4. Output ratings for the CS-144 alternators ranged from 120 amps to 140 amps. Very few parts, and no major parts, interchange between a CS-130 and a CS-144. In fact, there are even some major parts differences between early and late CS-144's. I do not know if a complete CS-144 can be retrofited to 86-91 Corvettes.

Also, the fact that both alternator case halves for a CS-130 are different for a CS-144 strongly implies that no internal parts will interchange.

By the way, although the CS-130D alternator was never originally used on a Corvette, I can tell you that no parts of a CS-130 and CS-130D are interchangeable. However, it might be possible to unit retrofit a CS-130D to an application originally using a CS-130. I can't say, for sure, though.

[Gregory G.]

Re: 1986 Alternator

The '86 CS130 alternator with a date code of 0055 would be deciphered as October 5, 1985?
What is the code numbers for the month of November and December based on September as number 9 ?