Third number on engine case

[studeb]

What is the stamped number under the engine type designation? In mine (type 901/14) it is 13393
Is this the engine builder? Or just some random number to make people guess?

[studeb]

Early morning bump.

[gregk1]

That # tells you what your motor is, like my 66 has 901-01 it is a solex motor(solex cams) a 901-2 is a S motor (S cams) 901-06 is a 130 hp 67 Motor probbly T cams And so on and so forth, My 911 shop manuel has those codes in them and so does Brad Andersons Book

[studeb]

Maybe i was not clear, i am talking about the number under the type designation. i know that 901/14 is a 68 type L motor.
What is this other number (13393) stamped below?

[djpateman]

This image provided by Bob Fleming shows the three engine #'s seen on the 2.0 motors. The engine serial # is bounded by stars, the engine type # is 901/xx, and the engine build # runs from 1 to about 30000.
The build # is simply the build sequence number from the engine shop. For the early 901/01 engines it was 100 less than the serial # since the production engine numbers started at 900101. As new engine types were added there was no relationship to the engine serial #. Here is some of the the data I have collected:
901/01 900128 28
901/01 900129 29
901/01 900236 136
901/01 900661 561
901/01 900685 585
901/01 901109 1009
901/01 901363 1263
901/01 901449 1349
901/01 901467 1367
901/01 901954 1854
901/01 902016 1916
901/01 902409 2309
901/01 902461 2361
901/01 902562 2462
901/01 902589 2489
901/01 902628 2528
901/01 903022 2922
901/01 903154 3054
901/01 903256 3156
901/02 960151 3584
901/20 906106 3629
901/05 907041 3879
901/05 907059 3900
901/20 906137 3979
901/05 907137 3984
901/05 907183 4036
901/05 907203 4056
901/05 907316 4172
901/05 907540 4405
901/05 907609 4474
901/05 907849 4714
901/05 908164 5032
901/05 909136 5189
901/05 909445 5703
901/02 960306 5873
901/02 960375 5998
901/02 960377 6010
901/02 960407 6052
901/05 909857 6099
901/02 960492 6225
901/05 909914 6697
901/02 960841 6821
901/02 960913 6895
901/02 960927 6925
901/02 961030 7150
901/02 961095 7240
901/06 ______ 7269
901/02 961208 7464
901/06 911305 7558
901/02 961390 7782
901/02 961687 8316
901/06 911718 8504
901/02 961942 8744
901/02 962082 8987
901/06 911951 9044
901/02 4080029 9272
901/06 3080031 9277
901/02 4080111 9423
901/02 _______ 9525
901/03 2080005 9547
901/14 3280123 9874
901/07 3180047 9906
901/14 3280234 10234
901/17 _______ 10584
901/06 _______ 10743
901/02 4080430 10923
901/14 3280376 10958
901/14 3280442 11233
901/14 3280461 11397
901/14 3280529 11677
901/03 2080552 11710
901/14 3280620 12050
901/14 3280670 12194
901/14 3280822 12976
901/02 4080919 12986
901/17 3380223 13016
901/02 4080941 13108
901/14 3280920 13393
901/02 4081110 13965
901/17 3380303 14124
901/02 4081172 14233
901/14 3281356 15372
901/06 _______ 15373
901/02 4081419 15415
901/02 4081449 15552
901/14 _______ 15841
901/17 3380402 16015
901/10 6390001 16250
901/10 6390050 16339
901/10 6390067 16410
901/16 6195052 16416
901/16 _______ 18638
901/16 6195563 19205
901/09 _______ 19692
901/16 6195715 19789
901/16 6195728 19821
901/03 6190553 19846
901/10 6391067 20928
901/09 6291062 21168
901/09 6291092 21324
901/10 6391343 22398
901/10 6391344 22399
901/10 6391515 23256
901/10 6392102 26274

Everyone that has a 2.0 motor with any 901/xx engine type is encouraged to contribute their combination of 3 codes to my list. We can learn a lot about how these engines were built. It seems to apply until the end of 1969 model year, then it was discontinued.

Dave

[djpateman]

Made a correction. Still looking for additional data. Surely a few members have a 2 liter they can check.

[ttweed]

I had 901/02 Ser. #960841 and it had the 4 digits "6821" stamped under the type number. I have never been able to figure out what the relationship was of those 4 digits to anything else, and no one on the Early 911S Registry has come up with anything solid about them when it has been discussed there.





TT

[djpateman]

Some additional data, many thanks to the members sending in this info:

Added to list above

[techweenie]

Another data point from a car I looked at yesterday:

901/14 3281356 15372

This engine is residing in a '70T, so if the owner of the '68 911L who needs it can be located, I can possibly facilitate a reunion.

[djpateman]

Thanks Bill. Very interesting to note that this engine was built immediately before another in the list. Unfortunately, the other engine was seen on eBay back in 2006, and the serial # was not obtained. Two different engine types. My guess is that they were building several engine types at the same time so the engine types could be random in the build sequence.
901/14 3281356 15372
901/06 _______ 15373

[Jagshund]

I would be glad to provide my own information to this worthy endeavor, but the build number on the engine currently installed (and included in the purchase of) my vehicle does not match that of the CoA; C= 338--- 901/17 and engine is a 328--- 901/14.

[Jagshund]

Okay, I lied. Anyone who's seen my site knows that the engine is NOT installed at the moment but sitting on the basement floor. And if I could tap that thing for oil I'd be rich . . .

[djpateman]

It does not matter to me if the engine does not match the car. The three numbers on the engine block are sufficient. I believe that all type 901/xx engines except those for the 914/6 and perhaps some of the racing engines have the engine build #. Does anyone have a type 911/xx engine with the build #?

[Jagshund]

In that case, here are the numbers:

901/14 3280461 11397

I looked up the numbers; apparently this is an extremely rare engine (hand built by The Doctor himself while single-handedly winning the 24 Heures, blindfolded). It's likely worth upwards of $100,000 which roughly translates to about 3 Euros.

Might make a good paperweight.

[djpateman]

Some new data, many thanks to the members sending in this info:
901/10 6390050 16339
901/16 6195728 19821

[djpateman]

drat, a double post, that is okay, I'll add yet another I found
901/02 961942 8744

BTW, I noticed in a post by Bill Noon that the build #'s for the type 901/10 engines starts @ 16250.
That seems reasonable, however I have to ask: is there is a source for such information?

[djpateman]

A few more I found

Added to list above

[djpateman]

I started a new thread over on the Early S Registry:

http://www.early911sregistry.org/forum/showthread.php?t=24913

That forum has a lot more of the owners of these engines, and I am keeping that list (in the first message) up to date. There is a lot of intersting information to be found in these numbers.

[Grady Clay]

As I have always understood this number, it is an ‘internal sequential number’ that is related to the engine number.


The sequence of numbering the case halves during manufacture are:

The casting numbers and casting dates are cast-in-place during the casting process. The case halves do not necessarily have the same dates or revision (R-number).

During the machining, the ‘matching haves’ numbers are stamped in the top of each case half. These are typically 2 or 3-digits.

I think this ‘internal sequential number’ is stamped about the same time. This allows tracking of the case before it is assigned to be a ‘T’, ‘E’, ‘S’, ‘L’, etc. This internal sequential number seems to usually be higher than the last digits of the engine number. I’ll speculate the difference is cases that didn’t pass inspection.

There are examples where there is a large difference between the internal sequential number and the engine number. I’ll speculate these were re-worked cases that were cycled back into production.

The ‘engine number’ is probably assigned just prior to assembly. This is necessary because a ‘T’ and ‘S’ are assembled from different parts. The engine number also tells the model year, model Type (you can correlate with the type number 901/05, etc.), if for a Sportomatic, etc.

The 6-digit engine numbers used unique numbering sequence for telling the type. The 901/02 911S add an “S” at the end of the number. Starting with the ’68 model year (7-digit), the engine numbers have digit place for type purpose. This was continued with ’69 and later engines but with a slightly different system.

I don’t think there was an association to a specific VIN until it actually went in the car.


I don’t recall exactly who told me this. It probably was a sequence of factory people over the years.


Dave,

I Just inspected 901/01, *900129*, 29 and it has case half matching numbers 52. I’m pretty sure this is the 29th 901 engine built. I think the “1” in the fourth digit is to not seem like this engine was within the first few built. This engine still has the boss on the chain housings drilled down. The difference between 29 and 52 may be scrap, damaged during machining or ones used for testing.

Here are four more 901/05s:
901/05 907919 4784 (virgin with about 70K mi.)
901/05 909130 5183
901/05 909298 5414
901/05 909790 6429

Best,
Grady

[djpateman]

Thanks Grady, your help is greatly appreciated. If I can respectfully disagree with some of your statements, I'll put forward my own theory to test.

The case half matching numbers were the first to be stamped, and probably only to good finished sets; that way the machine shop would have a record of how much good production they finished. That number I have only seen in 3 digits so far; any better data out there?

I think that once the engine was finished assembly, and passed testing it would receive the serial number, type # and build number at the same time. The matching halves number would be randomized at this point to some degree, but would generally follow as matching cases were converted into finished engines. Certainly they would have had to have been well ahead on machined cases before assembly. Besides, I'd bet the development cases would have the matching halves as well, thus accounting for over 30 of them.

The first PRODUCTION engine was 900101 and build # 1. All earlier serial engines were development engines and did not have build #'s; the only development engine I know of is 900032. So as production progressed, the type 901/01 engine serial #'s and build numbers were in lockstep (offset by 100) at least as high as build 3156. By build # 3629 both 901/02 and 901/20 engines were in production and contributing to the build #'s. However, large sequences of engines were built in lockstep after that. Consider the 379 engines between:

907540 4405
907919 4784

The fact that the serial #'s and build #'s are so often synchronized I think means that they are assigned together. I agree that serial # and VIN # are only generally related, just as the serial #'s and case matching #'s; they would only be so many cases or engines ahead of the next production stage, but out of that number, the pick would be almost random.