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So I am in the process of rebuilding 2ea Mc49E and the blocks are nearly identical with exception of the one on the left....See pic Now is that strange or what? Never seen this before, it is like the mold was only half modified.
Anybody seen this before?
Scott

Scott ., did any real .. mc49s come with the circle casted in like a saw block .. ?? also do you have any idea how many times a mold was used .?? they didnt have thousands and thousands of molds did they .. ??

I don't know how many molds they had but Bob Nicholson told me that he had to rent 5 of the largest U-Haul trucks to move just the tooling he bought from Los Angeles to Prescott when they were closing things down in the early/mid 80's. He said what he bought was just a tiny fraction of what was available at that time.

Scott,
having worked in the mold making / molding industry for many years, I have seen this before. In the molding industry, having multiple mold halves increases production through-put, due to the heating, cooling / demolding process. it also aids in mold maintance / repair and cutting-in new engineering changes. like wise in sand casting, have multiple masters speeds up the mold making process. so it in not surprising that two mold halves of different revision levels would get mixed. not that uncommon, except some quality control guy let this one slip by.
Tom

The 49C had a full oiler nub. They eliminated those with the late 91B1's and Mc92's. The oiler nub lays right at the mold parting line so half is in one side of the mold and half is in the other side.

This one intrigues me because half of the mold has the nub and the other half does not. It also does not appear that this is a pull in the mold either and to remove material from a mold is difficult because you have to fill space. It is easy to add material/features by re-machining but filling a space with weld in a hard tooled mold is not a common practice so I would imagine they had to re-do the whole half of the mold. The rest of the block is identical so maybe they messed up and forgot to remove the back half of the nub from the new mold and ended up having to re-do it.

It is also possible that they had several cavities in the mold fir multiple castings and this was just one of them or maybe they even had multiple molds. It would help if anyone else has seen one like this.

Scott,
Pretty cool, thanks for sharing the picture of the odd block.
I have two 49Es, one NOS and both are completely different shapes compared to the two blocks in your pictures. Both of mine have the "normal" shape to the fins on the head rather than the big rounded off shape on your blocks. Both of mine also have the complete nub on the back of the block.
Steve O'Hara