Need clarification on date codes

[Dennis H.]

Hi
I was checking some date codes on my 73 and bouncing them against the TM/JG manual. The item that has me confused is the fan clutch, my date code is D2873SC.

On page 157 it shows an example in Fig. M 18.6 of a 73 fan clutch with date code K2272SC and the judging guide says this is 22 Oct 72. If I walk K (Oct) back to A I end up with a start month of Dec.

On page 109 a cylinder date code of K is November which is correct if I walk that back to the letter A the start month is January.

With me so far? Did Schwitzer Corp start their month codes in Dec, Dec=A?


A - Dec
B - Jan
C - Feb
D - Mar
E - Apr
F - May
G - Jun
H - Jul
I - Aug
J - Sep
K - Oct
L - Nov

Thanks
Dennis

[Terry M.]

Re: Need clairification on date codes

Hi
I was checking some date codes on my 73 and bouncing them against the TM/JG manual. The item that has me confused is the fan clutch, my date code is D2873SC.

On page 157 it shows an example in Fig. M 18.6 of a 73 fan clutch with date code K2272SC and the judging guide says this is 22 Oct 72. If I walk K (Oct) back to A I end up with a start month of Dec.

On page 109 a cylinder date code of K is November which is correct if I walk that back to the letter A the start month is January.

With me so far? Did Schwitzer Corp start their month codes in Dec, Dec=A?


A - Dec
B - Jan
C - Feb
D - Mar
E - Apr
F - May
G - Jun
H - Jul
I - Aug
J - Sep
K - Oct
L - Nov

Thanks
Dennis

Dennis

As a GENERAL rule of thumb: Cast dates use I = September

Stamped dates do not use I because of the potential confusion with the number 1

Thus for stamped dates:
A= January
B = February
C= March
D = April
E = May
F = June
G = July
H = August
J = September
K = October
L = November
M = December

Thus your fan clutch is dated April 28, 1973.

It is wise to rememvber this is a GENERAL guide, and there are exceptions -- as with everything else we find on Corvettes.

[Dennis H.]

Re: Need clairification on date codes

Got it, I figured it was something on my end I was not understanding.

Thanks

[Terry M.]

Re: Need clairification on date codes

Got it, I figured it was something on my end I was not understanding.

Thanks

Dennis,
I should point out that this "convention" defies all logic in that if one can confuse the characters I and 1 in a stamp, why can they not be confused in a casting? Casting numbers are much less precise than stamped characters, so the chances of confusion are greater.

It makes no sense; it is just the way they did it.

[Michael J.]

Re: Need clairification on date codes

Yes Terry, but JB Weld comes in very handy on cast dates........

[Dennis H.]

Re: Need clairification on date codes

Yes Terry, but JB Weld comes in very handy on cast dates........

That's old school, I flew to OK back in the pre internet days to look at a 66 427 car that was VERY mispresented, they used a hammer and chisel to remove the engine casting numbers. When I pointed that little fact out to the owner he said oh yea well the story goes that the engine was "hot" at one point back in the 70's. I thanked him for his time and went back to the airport.

[Terry M.]

Re: Need clairification on date codes

Yes Terry, but JB Weld comes in very handy on cast dates........

I wouldn't know about that of which you speak.

[Pat F.]

Re: Need clairification on date codes

Folks, here are some pages from the 1966 Judging Manual and you will note the exclusion of the letter I.