These engine block numbers on my 30’s don’t seem to add up to the S/N book any thoughts.... maybe manufacturing dates..... there are no S/N tags on these machines.
the BEST 30 looks to me like a 1440 welded on the top engine block but wanted other’s input 
Thanks!

The best guess that I have been able to come up with is that the series of numbers 6-11-28 and 11-23-29 and the dates that casting was machined. I have found number series like that on the back of some L/PL trani housings. Are both of the Cat machines San Leandro machines?
Thanks
Ken

I would agree, Date of either the casting or machining
cts

Casting date is cast in the casting, not stamped. The three digit number is the machining number, which is applied to all the parts machined as an assembly. In the case of a Thirty, the main case, the bevel gear shaft bearing caps, and the sprocket shaft caps, all would have same number.

the wide yellow is a PS it’s a late model for sure
the grey one I believe is a San Leandro  based off the older parts that match up to BEST models. It does have the Large track roller springs tho.....
the best obviously is a San Leandro (I think that 1440 is it’s S/N).....that was welded on the block in the picture.

I was thinking that they were date of casting also, that was a guess, the 762 on the top of the grey one tho always confused me tho ......

if they are casting dates then the 762 would be? Any guess??
thanks,
shaun

 

The 1446 is cast in block, not welded, It is casting number S-1446. applys to tractors serial numbers S-3101 to10536 (1925 to 1930) and PS1 to 13285 (1925 to 1931)
The date of tractor creation and serial number assigned, could be between 1 and 3 months after the machining date stamped in case. This is based on comparing machining date and tractors with serial numbers.

Thank you for the information