additional block stampings

[Gary S.]

I have a 3904351 4-bolt block, cast January 1967, pad decked, that has T037 stamped on the undersurface, and 10846 stamped on the front above the main. It also has some single digits like 4 or 6 stamped here and there.
Any ideas where those might have been done, and what they mean? I'd guess the T037 might mean Tonowanda 3rd of July.
Yes, that's a failing repaired crack on the bolt hole

Gary

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[Owen L.]

Re: additional block stampings

Because your block has been machined after originally done at Tonawanda, some of those markings could well be the rebuilding machine shop's work. Chevrolet did stamp the oil pan rail with various codes to indicate which piston size to install further down the line. My '72's 454 block had a number of these pan rail stampings though I don't recall if they were numbers or letters. I don't believe there were any other stamps in the block other than on the pad. John Hinckley wrote an article on the Chevrolet small block process that probably applied similarly to the big blocks.

[Patrick B.]

Re: additional block stampings

Are you sure the the block was decked? If so that is a shame. This was a never stamped over-the-counter block or short block. The T037 stamped near the starter mount was done by Tonawanda to indicate that it was parts dept block machined in March 1967. Look at the deck carefully. If it is very smooth without rotary milling marks, it is the original deck surface. The grain can be pretty faint. If it has rotary milling marks on the deck, then unfortunately it was decked by a the machine shop who put the 10846 stamp on it. That stamp is unlikely to be a Tonawanda stamp.

[Gary S.]

Re: additional block stampings

Owen and Patrick, thank you. Block has 8 sleeves, apparently had been sleeved and decked in the 1980's