Date code on Master Cylinder

[Jeff Y.]

If my car's build date is 11/5/72 (1972 coupe) what would the appropriate date range for the master cylinder be? I guess that is even a general question about the car that I could extend to things like exhaust manifolds, alternator, etc.

Thanks,

Jeff

[Rick A.]

Re: Date code on Master Cylinder

tyhpically, on most non-glass parts if you are in the SIX-MONTH range or less you are safe; glass is typically within 12 months - really need to be looking at JRM for all the standard deducts and date ranges

[Alan S.]

Re: Date code on Master Cylinder

Hi Jeff,
I'll reply to the master cylinder part of your question.
Using my 71 which was built in mid-January 1971 as an example; the date stamped in the machined area for the front brake line connection is 0 338. The 338th day of 1970... so about six weeks before the car was produced. I believe that's the date the cylinder was machined. In the picture the first digit looks like an L, but close up you can see it's a partial 0.
The cylinder has a date cast into the body too. But, I'm unsure how to read it. On this cylinder it's 149.
Perhaps someone can help us.
Regards,
Alan

[Jeff Y.]

Re: Date code on Master Cylinder

Sorry for the newbe question, what is a JRM and where do I get one?

[Rick A.]

Re: Date code on Master Cylinder

Judging Reference Manual - it provides information on suitable range of date codes for just about everything and provides information on "Standard deductions" for just about everything - very handy guide that can be purchased from the NCRS store on the bar above the page

[Patrick H.]

Re: Date code on Master Cylinder

If my car's build date is 11/5/72 (1972 coupe) what would the appropriate date range for the master cylinder be? I guess that is even a general question about the car that I could extend to things like exhaust manifolds, alternator, etc.

Thanks,

Jeff

If your car's build date is Nov of 72 my guess is that you have a 1973 car.

I suspect you meant Nov of 71.

Patrick

[David L.]

Re: Date code on Master Cylinder

Hi Jeff,
I'll reply to the master cylinder part of your question.
Using my 71 which was built in mid-January 1971 as an example; the date stamped in the machined area for the front brake line connection is 0 338. The 338th day of 1970... so about six weeks before the car was produced. I believe that's the date the cylinder was machined. In the picture the first digit looks like an L, but close up you can see it's a partial 0.
The cylinder has a date cast into the body too. But, I'm unsure how to read it. On this cylinder it's 149.
Perhaps someone can help us.
Regards,
Alan

Alan,

Doesn't the "149" represent the 149th day of the year? The year in your case would be 1970. I have seen the 3-digit casting date on 1963 and 1964 master cylinders but no indication of the year.

Dave

[Alan S.]

Re: Date code on Master Cylinder

Hi Dave,
I've done a search and found a thread from this past Fall,(including a post from you), about casting dates. I looked at John H's link in that thread and thought I understood the 'cast' dates, BUT, when I look at my master cylinder I can't have '149' make sense.
Apparently the same bad things that are happening to the outside of my aging body are going on in my brain too!
Pleasant thought for a Friday afternoon.
Regards,
Alan

[Terry M.]

Re: Date code on Master Cylinder

I have been trying for years to get someone to tell me the date code on the master cylinder the UAW installed on my 1970. Trim tag is A29 (Jan 29, 1970). The stamping on the forward port of the master cylinder is a single number 1. Any takers?

[Alan S.]

Re: Date code on Master Cylinder

Hi Terry,
Is it the index finger 1, or the next finger 1?
Regards,
Alan

[David L.]

Re: Date code on Master Cylinder

For what it's worth there are two interesting articles written by Hans Norberg in the Corvette Restorer Magazine.
"1967-1972 Corvette Master Brake Cylinders" in Vol. 17, No. 2 (Fall 1990), page 22-23
"1967-1972 Corvette Master Cylinder Revisited" in Vol. 17, No. 4 (Spring 1991), page 42-43

Dave

[Jeff Y.]

Re: Date code on Master Cylinder

Oops. Typo. Build date is Nov of 71. Not 72.

[Randy C.]

Re: Date code on Master Cylinder

For what it's worth, my '71 small block standard coupe has a build date of 12/15/70 (according to the shipping data; the trim tag says E14) and my master cylinder (known to be original) has a date of "0201" which is July 20, 1970. My original starter also has a July '70 date and many original parts under the hood, as well as most of the fiberglass parts where I can see the tag, have August 1970 dates. At first, this seemed to be quite a separation of dates between these parts and the build date of my car but I found out there was no production from about mid-September 1970 to late November 1970 which helps explain the date separation.

Randy C.

[Alan S.]

Re: Date code on Master Cylinder

Hi Randy,
What is the casting date on your master cylinder's body?
Regards,
Alan

[Randy C.]

Re: Date code on Master Cylinder

Hi Alan,
Where your casting date is on the body of your master cylinder, all I can see on mine is the number "1" where you appear to have a "9". The rest of the symbols on that line appear the same on mine as yours. I don't have anything below the "1" - no casting date, nothing. It's a power brake master cylinder (5480346) with the "PG" stamped into that semi-circle machined area in front. Just above the front brake fluid line (same place as yours), the date "0201", in small numbers (just like yours), is stamped into the metal. I have these things in my notes but it's been a few years since I actually looked at it so I just went out to the garage to look and re-confirm, and that's what I have!

Randy C.