I think this is correct original alternator for 1971 motor that it's mounted on. It seems to be charging and working fine at present. Can anyone help with ID or info on this unit? Also does anyone have suggestions on cleaning it and retaining the original factory stamps ? Thanks

 

I don't have all my resources here at the moment. It's a 1971 Oldsmobile engine, a 455 painted red? That alt is for a car with an external regulator. The real part# is where the adjusting bolt is, you have to remove that bolt, turn the alt up to see the #, date and amps. The 228 should be the last 3 numbers of the alt, like #1100228 or something. I think they stopped stamping them like that around 1967 or so. Then they used alpha letters. Take a pic where I told you of the #'s and post. Best guess is it's a 67 or older alt.

 

Can't be correct. Front and rear halfs are a mismatch.

 

Thanks guys been traveling so haven't been on the site in a few days. This is 455 motor that I came across on the cheap and just checking out what it is and isn't. My knowledge of alternators is very limited so I knew someone on here would know. Yes someone painted it red (partially anyway !) It does crank and run but beyond that is yet to be determined.

 

Need part number to help you further, or elaborate what type of vehicle you are working on. Thanks.

 

It's just a spare motor I didnt want to let get away it was so cheap. It's found a home on the engine stand for now. !

 

The front and rear half are correct. If your interested the original part number for a 1971 Cutlass externally regulated 37 amp Alt is 1100566.

 

I disagree. Rear end (slipring end) is from 10DN style alt. Front end (drive end) is from either 10SI or late 10dn style alt. It can not be a correct numbered alt
for his application or anywhere near original.

 

X2, I'm with Stellar on this, just as a point of info for others. I'm still pretty sure the 3 digit stamp is the last 3 numbers of the part. The yellow stamp I thought was a date code, never seen it on GM, but that's what I thought. When stellar mentioned it was a hybrid, I looked again, and you can see the front and back have like different textures or dirt or color or something. It is like rebuilt carbs, they just disassemble them, toss them in piles, clean them, and then put them back together again. So you could have an olds body, cadillac throttle plate, chevy truck air horn, mass rebuilders don't give a crap. I'm obviously not talking about stellar here, I'm talking about mass rebuilders like Cardone or whatever.

 

While its now certain that its an NOT OEM alternator I guess I will keep it just for it oddity. The motor is a non 442 G head 455.

 

While the front frame D.E. may not be with the original rear frame S.R.E. it was born with, it is still the correct case for a externally regulated 10DN alternator of that era. Open face 10SI (Systems Integrated) internally regulated alternators obviously had a different front frame. The rear frame S.R E. is also different with ribs on the outside case. I do not see why you think the housing that is pictured is not correct for a 1971 Oldsmobile. It is clearly not internally regulated, therefore the housing is correct for a externally regulated application. If the original poster can provide the stamped part number I can confirm what the application is for.

 

Bug man wants to know if it is correct original alt. It is not, no matter what the number is.

 

The question The Bug Man ask is if anyone can ID or give info on the photo'd alternator. As I previously posted, without the stamped part number you can only guess the application, but you can confirm from the photo's it is period correct by its front and rear frame. The only issue I see is the lack of "Delco Remy" on the rear frame. I posted photo's of a original correct 37 amp alternator for a 1971 Cutlass showing the part number. The photo's of the alternator in question and the photo's I posted are identical. He said he thinks it is the correct original alternator for 1971, he did not ask or state it was a 1971. Again if the stamped part number is posted I can confirm the application. Please elaborate why you think it is not correct for 1971. The front and rear frame housing photo'd, is the standard design for a myriad of externally regulated alternators over the years.

 

Rocketdevo, is the 1100566 correct for 71 with air conditioning or non air? Thanks brandon reynolds

 

Pics not identical. Pics of 10DN drive ends. Bug man has late style drive end on an early style slipring end. How can your 566 be identical to The Bug Mans pic? It just isn't so. Granted his alt will work on external regulator apps, but it is not (correct) for any specific application.

 

The second photo from the original poster is Identical to the second photo I posted. I don't how you can not see that. I think you are confusing "late and early" style with externally and internally regulated alternator's. The front frame's are all basically the same unless it is an open face alternator. The rear frame if it is a externally regulated Alt. is what I and the original poster have pictured. If it is an internally regulated Alt. it will have ribbing, as the photo you have posted shows, on the rear frame. This applies to 1971 and older alternators. In 1972 I will grant that externally regulated Alt's had the ribbing on the rear frame, as all Oldsmobile's were externally regulated that year. Ribs on the rear frame are a tell tale sign that it is a internally regulated alternator unless it is the 1972 model year. The 1100566 is correct for 1971 Cutlass Non AC. The 1100569 is correct for AC. The 442 standard Non AC is 1100934 and 1100935 for AC and HD cooling auto's.

 

I think you must be toying with me. Of course I can see the 2nd pics are the same. That is not the point. I am not confused by anything here. I agree with the info you have provided. My pics show 2 alts that are both externally regulated. They have different drive end frames. Even though they are "basically the same" they are different. I don't know how you can not see that. If I were to switch the drive end frame of the 2 alts pictured they both would not be correct. That is what the OP pic shows (switched frames), so it can not be correct. The DE frame on his alt never came stamped with the 566 #. Even though the rear ribbed frames of the internal and external look alike there is a very slight difference, but I would guess you know what that is also.

 

I just want to get to the bottom of this and make sure the right information gets presented. I may not be understanding what you are saying correctly.
I do see that the second photo you posted has two different front D.E. frames. The one on the left in the photo I believe is 1968 or older. The one on the right is 1969 or newer. I concentrate on 1969-1972 models mostly. In the first photo you have two alternator's and are referencing the rear S.R.E frames. The Alt. on the left is externally regulated, and the Alt. on the right is internally regulated, except in the 1972 model year. I do know there is a difference between a 1969 ribbed diamond back as oppose to the 1970 diamond back. Are you saying that the ribbed Alt. on the right is correct for 1971 externally regulated? The second photo of the Alt. on the right you posted is the second generation which is correct for 1971, and it looks the same as the original poster's photo's.
The original poster would be doing a great service if he would post the part number on the said alternator? Considering that is the question put forward and he has not, the true application of the Alt. will never be revealed.

 

Looks like we have an obvious communication problem. I suppose the point is moot anyway. In Bug Mans post the rear case with the diodes is aftermarket and not OE. The red positive post insulator is not original either. The black 228 stamp and the yellow stamps are a remanufacturers numbers and of no value to retain. The drive end case may also be aftermarket since no numbers have been forthcoming, and it may not even have any numbers stamped in it. Bug Man can clean it any way he wants and not worry about retaining the black and yellow stamps. It will look better cleaned, but it won't increase the value of the unit much. He should be more concerned about the location of the battery ground cable. I feel terrible that I can't explain the difference in the front Drive ends to you, but I will try again. In my 1st pic 2 alts are shown. Both are externally regulated. The one on the right with the ribbed back case is a 1972. The one on the left is earlier. The difference in the rear cases is obvious, ribbed vs non ribbed, but that is not what I am referencing. I am showing the difference in the front drive end cases. If I were to disassemble the 2 units I pictured and reassemble them interchanging the ends one would look like the one in Bug Mans post. And now neither of the alts would be correct or desireable to someone wanting an original or restored alternator to be a correct alt for their car. I hope this explains it better and I hope Bugman doesn't spend too much time trying to make his alt into something for a show car and relocates the ground instead.

 

Hello Stellar, you are correct sir. I misunderstood you and kept assuming you meant something else. I now feel terrible that I did not see what you saw. The alternator still mounted on the engine did not draw my eyes to it until you prompted me to take a closer look with your last post. I now clearly see they are a mismatch. I apologize for the misunderstanding and for rebutting you unnecessarily. Yeah that ground looks bad in that location.

 

Rebutting is good. No apology needed or wanted. You supplied some good info for others reading the thread. Info is what the forum is for.