Date Code Clarification

[Doyle L.]

I'm currently replacing the aluminum radiator expansion tank on my 1969 Corvette; The vehicle is an early 1969 (B24) September 24 1968 build date.

The aluminum expansion tank has 3016340 and 68 K stamped on the end. I feel confident this is the original tank, the part number is correct but I have question about the 68 K stamp.

Question; Is K for the month of October?

[Gary B.]

…. Question; Is K for the month of October?

Yes indeed it is.

Gary

[Gary B.]

Doyle,

By any chance do you have the shipping data report for the car? It would be interesting to see what date that has for when the car was produced.

Gary

[Mike E.]

Likely the original was defective several months into the car’s life, and the car received a service replacement under warranty.

[Patrick H.]

Note that the reproduction overflow tanks are not perfect. As such, you might want to just take the small date code deduction rather than replacing it.

[David H.]

Note that the reproduction overflow tanks are not perfect. As such, you might want to just take the small date code deduction rather than replacing it.

Doyle

Welcome to NCRS Tech Board!

As Patrick noted, your current tank is likely better than a reproduction.

An Expansion Tank would be judged under our Matrix Judging System (C.D.C.I.F.). Appearance of Originality is judged against Configuration (how things are shaped, stampings, etc), Date (part isn't younger than car), Completeness (everything is there), Installation (installed correctly), and Finish (surface coating or lack of surface coating) against how that car left factory. Each of those CDCIF areas is evaluated at 20% of score.

If 10% of Originality points remain after judging, then Condition is judged. There are 4500 total points in Flight Judging.

There are 8 Originality points tied to your Expansion Tank. (sample judging sheet below) If Date alone is your issue, that would result in a 20% point Originality deduction or 2 points. You might however, also be subject to Condition point deductions.

A NEW reproduction tank might have Configuration and Date issues (reproduction might get stamped). Both Configuration and Date issues would generate a 40% or 3 point deduction. As it is new, no deduction for Condition.

Above is a simplified look at our judging process - sort of "pick your poison".

Me, I'd stick with your current tank if Condition is good.

Dave


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