Master Cylinder Date code

[David J.]

On a 1969 master cylinder, how do you decode the date code? Looking at a master with the date numbers of 241. Does this stand for the 241st day of 365?
The only numbers on the master are the part number which is 5455509 which is correct for manual brakes and the another set of numbers are D6 and 241.

[Joe L.]

Re: Master Cylinder Date code

David-----

If you are talking about the CAST-IN number being "241", then I believe this to be a julian date code without reference to a year. So, if I'm right, the "241" does refer to the 241st day of the year. Since we don't know what year it refers to we don't know if it's the 241st day of 365 or the 241st day of 366. Without the year, the day of the year is fairly meaningless from a restoration perspective. Of course, I suppose one could surmise that if one had a car built, say, the 241st day of ANY year, this master cylinder would not be correct for it. I don't think that this number is judged, though.

There is sometimes a STAMPED-IN number found on the front brake fitting machined boss. If present, it will be seen in very small characters and this stamping DOES have a julian date code WITH reference to year.