Head Manufacture Date

[Eneto-55]

Is there a way to tell when a head was manufactured?

For instance, the '55 engine I have in my P15 has the following numbers & notations on the head: 12.10.54; 1616823-4; and a 'D' & 'N', with an arrow below it pointing to the 'D'.  I assume the first is the date code, which would make sense for a '55 engine.  This head also has the smaller hole for the temp gauge, because the '55 models had an electric sender unit.

 

I have another head which I believe to be out of my 49 1st series (P15).  It has the following notations on it. 12-1; and 1120803-8.

 

The reason for asking is because my brother has an engine from a '51, which also used the capillary style temp sending unit.  We had some things stolen from our cars in our parent's back yard, and we're trying to establish if the head I have is from the 49, or the 51.  The one I have I had moved into the shop before already, possibly years ago, but I don't remember when.  (My extra bell housing has also disappeared. - I assume stolen when the other stuff went missing.)  Both of these engines were torn down back in the early '80's.

Thanks.

[JerseyHarold]

The casting date is December 10,1954, which would be correct for a '55 engine.  The D and N refer to day shift or night shift, and the 1616823 is the casting number (which may or may not correspond to the part number), and '-4' refers to which mold was used in the foundry  (#4, in this case).   HTH

[Eneto-55]

Any ideas regarding the second one?  (That is the one that may be my brother's.)  I suspect that they didn't put the full date code on them back that early.  I was hoping someone who has a 51 model could tell what sort of notation is on theirs. (Or someone else with a known P15 head.)