CRG Discussion Forum

Camaro Research Group Discussion => General Discussion => Topic started by: x66 714 on April 06, 2021, 12:10:00 PM

Title: 1969 master cylinder, original or reproduction
Post by: x66 714 on April 06, 2021, 12:10:00 PM
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
Title: Re: 1969 master cylinder, original or reproduction
Post by: firstgenaddict on April 06, 2021, 12:25:32 PM

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.
Title: Re: 1969 master cylinder, original or reproduction
Post by: x66 714 on April 06, 2021, 12:26:43 PM
Thank you. I'll have to find a known original to compare...Joe
Title: Re: 1969 master cylinder, original or reproduction
Post by: 69Z28-RS on April 06, 2021, 12:46:10 PM
I was under the impression that the reproduction castings all had the same 'cast date' on the side??
Title: Re: 1969 master cylinder, original or reproduction
Post by: x66 714 on April 06, 2021, 12:58:23 PM
I don't recall seeing a date code where it should be...Joe
Title: Re: 1969 master cylinder, original or reproduction
Post by: jdv69z on April 06, 2021, 01:54:52 PM
Here's mine. Oct 68 10B
Title: Re: 1969 master cylinder, original or reproduction
Post by: 69Z28-RS on April 06, 2021, 02:08:46 PM
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'...
Title: Re: 1969 master cylinder, original or reproduction
Post by: Danzo on April 06, 2021, 10:50:57 PM
Joe, post some pics of what you got,
Doc
Title: Re: 1969 master cylinder, original or reproduction
Post by: x66 714 on April 06, 2021, 11:30:56 PM
Here's a few pictures. I might need to take it off as the camera flash makes it too much. Thank you, Joe
Title: Re: 1969 master cylinder, original or reproduction
Post by: jdv69z on April 08, 2021, 01:29:43 PM
Mine master looks like it's stamped directly on the cylinder casting, not a machined surface?
Title: Re: 1969 master cylinder, original or reproduction
Post by: Stingr69 on April 08, 2021, 02:06:31 PM
My original "US" master cylinder with a julian "239" date code for 239th day of '68 on a 10A build.
Title: Re: 1969 master cylinder, original or reproduction
Post by: Stingr69 on April 08, 2021, 02:15:13 PM
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.