Author Topic: 1968 Manual Drum Brake Master Cylinder Date Code  (Read 6311 times)

stovebolt

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1968 Manual Drum Brake Master Cylinder Date Code
« on: January 29, 2010, 07:58:47 PM »
The attached picture is of my original 1968 manual drum brakes master cylinder casting number 5452310, application code BS. The date code is C8 8 (March 8, 1968).
The foundry code is T37. My car is an 04A Norwood car. Every master cylinder date code I've seen so far has been in the Julian form. Did the two date code formats co-exist or did one supersede the other?

68Zproject

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Re: 1968 Manual Drum Brake Master Cylinder Date Code
« Reply #1 on: January 30, 2010, 04:52:43 AM »
That's a casting date code.  The assembly date code (on mine) was Julian.
68Z28

stovebolt

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Re: 1968 Manual Drum Brake Master Cylinder Date Code
« Reply #2 on: January 30, 2010, 02:42:24 PM »
Thanks for the info. Where would I find the assembly date stamped on my M/C? Joe.

68Zproject

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Re: 1968 Manual Drum Brake Master Cylinder Date Code
« Reply #3 on: January 30, 2010, 09:52:32 PM »
I have no idea on those mcs.  Mine was power front disc.
68Z28

stovebolt

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Re: 1968 Manual Drum Brake Master Cylinder Date Code
« Reply #4 on: January 31, 2010, 01:02:51 PM »
Is it possible that master cylinders never had an assembly date stamped? Also, I can see a faint number stamped on the machined boss at the front brake line fitting. Any ideas what that might represent? Thanks.

JohnZ

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Re: 1968 Manual Drum Brake Master Cylinder Date Code
« Reply #5 on: January 31, 2010, 03:54:44 PM »
Is it possible that master cylinders never had an assembly date stamped? Also, I can see a faint number stamped on the machined boss at the front brake line fitting. Any ideas what that might represent? Thanks.

In the Corvette restoration world, we also see very tiny stampings on the machined boss around the front outlet, occasionally in 1968 and more frequently in 1969; that's a julian assembly date. If you look VERY carefully at the photo below, you can see a "3" and remnants of several other numbers on a '68 master cylinder boss.
'69 Z/28
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68rs327conv

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Re: 1968 Manual Drum Brake Master Cylinder Date Code
« Reply #6 on: January 31, 2010, 05:12:36 PM »
In the Corvette restoration world, we also see very tiny stampings on the machined boss around the front outlet, occasionally in 1968 and more frequently in 1969; that's a julian assembly date. If you look VERY carefully at the photo below, you can see a "3" and remnants of several other numbers on a '68 master cylinder boss.

I can make out 353

Mike
[/quote]
Mike
68 RS Conv 327/210hp, Powerglide Factory AC

stovebolt

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Re: 1968 Manual Drum Brake Master Cylinder Date Code
« Reply #7 on: February 02, 2010, 04:59:28 PM »
If you look closely at the 12 o'clock position on the boss, you'll see an assembly date of 78 which is the Julian date for March 18. The master cylinder was cast on March 8 and the car was built during the first week of April, 04A. Thanks to all for your input. Joe.