1969 master cylinder, original or reproduction

[x66 714]

My original master cylinder got lost some years back. About 12 years back I purchased one on e-bay. It's the disc brake "US" type. Anything I can look at to determine if it's an original of a reproduction? Thank you, Joe

[firstgenaddict]

Compare the US stamp, from what I remember the U was not the same on the originals VS the reproductions.
If not mistaken it was Narrower and taller on the repro.

[x66 714]

Thank you. I'll have to find a known original to compare...Joe

[69Z28-RS]

I was under the impression that the reproduction castings all had the same 'cast date' on the side??

[x66 714]

I don't recall seeing a date code where it should be...Joe

[jdv69z]

Here's mine. Oct 68 10B

[69Z28-RS]

I don't recall seeing a date code where it should be...Joe

The 'cast date' on a Delco MC is on the opposite side from the casting number, and it's in the form of a 'day of the year'...

[Danzo]

Joe, post some pics of what you got,
Doc

[x66 714]

Here's a few pictures. I might need to take it off as the camera flash makes it too much. Thank you, Joe

[jdv69z]

Mine master looks like it's stamped directly on the cylinder casting, not a machined surface?

[Stingr69]

My original "US" master cylinder with a julian "239" date code for 239th day of '68 on a 10A build.

[Stingr69]

Mine master looks like it's stamped directly on the cylinder casting, not a machined surface?

It was a machined pad originally but rust got to it.  Your stamp is consistent with mine and we are about 1 week apart.