??? *NM*

[Roy B.]

[Gary Bishop]

Relating to What????? *NM*

[Roy B.]

Re: Relating to What?????

Relating to any cast iron part as to what (shift) when that part was made ( it's just trivia )

[Gary Bishop]

Very Interesting!! Good Stuff!! *NM*

[mike cobine]

Re: Relating to What?????

When you get those questions from people who ask:

- my block is D172 and the stamp is F0417RC. Can my intake with D172 be ok for judging?

You can look at the shift timestamp and see if the intake was cast before or after the block. An intake cast the last shift probably didn't make it on a block cast in the first and assembled in the second or even third shift.

[H S.]

Re: ???

Roy,
I think you will find the clock is only 10 hours.

H P Shuttleworth

[Roy B.]

Re: Relating to What????? thanks Mike *NM*

[Mark G.]

Roy - This Was Covered

Roy -

https://www.ncrs.org/forum/archive21.cgi?review=163480

Does your engine block have a number next to the large GM at the rear housing area. If so, does it match the cast in number on the bottom surface of the fuel pump mounting flange. Thanks, Mark #35760

[John H.]

Re: Roy - This Was Covered

This is the area and the number Mark's referring to:

[Tom R.]

Re: Roy - Nice photo

That's it! Great resolutin

[Joe R.]

Re: ???

Hi Roy:

The way this has been explained to me differs slightly from what you describe, but maybe the procedures evolved over time. My understanding is the following:

First shift = two flat head screws
Second shift = one flat head and one round head screw
Third shift (rare) = two round head screws

The clock symbol indicates which hour of the shift. So, in the photo below, one would conclude that the casting was made during the first hour of the first shift. This information was encouraging to me because the pad stamping on my 67 small block says it was assembled on the same day that the block was cast. Having the block cast during the first hour of the first shift makes that more feasible.

By the way, I always thought the shift coding of the screw heads only applied to the removable plate that was used to show the casting date (my casting date has two flat head screws as well). It seems odd that they would change the screws on the plate for the casting number at every shift change, but maybe they did. Hopefully some of the others on the board can comment on this.

[Roy B.]

Re: ???

(It seems odd that they would change the screws on the plate for the casting number at every shift change, but maybe they did. Hopefully some of the others on the board can comment on this)

I think it was so that if a problem arose they knew which shift was responsible . It's like seeing different GM1 or GM3 or GM7 cast into other parts ( that was done so if again a problem arose "like a flaw in the casting" they knew which mould was defected and would destroy that mould ( say GM3)

[John H.]

Re: Screw Heads

Joe -

That's correct:

Two flat head = 1st
One flat, one round = 2nd
Two round = 3rd

Here's what the date marker looked like that was screwed to the pattern - each individual brass character was soldered to the brass plate.

[Joe R.]

Re: Screw Heads

Hi John:

Was the shift coding with the different screw heads used only on the two screws that held the date code plate?

Roy's summary seems to say that the screws holding the casting number tag were also coded, but this surprises me. I can't see why the factory would change the screws on the casting number insert every shift.

[Rick S.]

Re: Screw Heads

John,
Above my cast date code (E317) there is another code number (1) which has one screw. What does this denote?
Rick