The Stovebolt Site Forums The Parking Lot '60-'66 Trucks What is ' 17 716 '

These 2 numbers are stamped on drivers side
of block , about dead center, on a 3769716.

Block casting code (3769716) on a 1958-1962 235 truck engines and some car engine.

Find and post the block casting date, and the head casting code and date. That might better ID the engine?

locations of codes

OK. I get that it is June 10, 1960
was just curious about the 17

Just spitballing here, but may just be a code for the pattern used for that particular head casting. I'm sure there wasn't just one pattern for all the 3769716 heads.

As Kevin indicates, I would agree and say the 17 is the mold/pattern number and 716 is possible foundry code. OR vise versa because 716 is the last three numbers of the casting number. These were for traceability in case of failures/issues and quality control inspection recording. (mold wear)

Cast numbers with screw head or button head on either side indicates changeable inserts, called tags, attached to the pattern, in a built in recesses. These can include cast dates, pattern number, molding line conveyor (shaker), pointer and casting numbers. Some hardly changed, and they were soldered on. When you see a number like GM3, that is a pattern number. If this head or block has a GMX number, then the 17 and/or 716 must be something else.

GM had various ways of delineating the shift.
The shape of the screw heads on the ends of the casting date tag was: two flat head for 1st shift, one flat head and one round head for 2nd shift and two round for the very rare 3rd shift. Some screw heads/solder blobs are in the middle of the date.

Another method was "D" for day, "N" for night and "T" for third. These were letters wandering around near the date.

There was also a "casting clock". Where Zero, or two dots, was 1st hour of shift. The pointer points to the hour of casting pour. It is thought that the pointer screw head could show what shift.

There are variations, change in methods, anomalies and factory screw ups which can cause numbers matching issues.

All these letters and numbers and symbols have been seen by us on our engines thru the years, but not all of us knew what some of them were for sure.

I'll chalk it up to mystery we'll never solve.

yep

I think it will be solved by someone on here sooner or later.