I have two blocks from 1923. One is July and the other is December. The casting boss where the numbers are stamped is different between the two. The earlier one cuts back under itself while the later one goes straight all the way down to the water inlet section. I think I have seen these interchangeable for several years. Or was there a cut off date?
Also, were the numbers always 1/4" high ... or did the factory use other sizes?
If the number is the sole method you are dating it by that could be a problem. Replacement engines came unstamped, or perhaps somebody in the past needed something to match their title . . .
Top image matches the profile of the pre-August coupes, while the lower image matches the profile of the coupes introduced in August. That is my theory and I'm sticking with it.
What about runabouts?
And .... the number stamping height?
Stamps are 1/4" according to Ford Service.
According to Bruce's book, about Sept 1923 the Ford script was left off the block on some production.
Has anyone ever seen one with two numbers as described in the service book?
Thanks! That's what I was looking for.
Sometime in 1923, in about September according to Bruce's book, the engine block casting was changed to remove the, Ford Made In USA, and the engine number boss was changed into a more rectangular shape. Mark, if this holds your July 1923 USA block should have the Ford script and your December 1923 should not have it. Also Ford stopped using a casting date around this time so your July block should have a casting date and your December block should not have one.
On my '14 block there is no number, it is assumed this was a replacement engine never installed.
Likely a replacement block only.
Fully assembled factory engines always had serial numbers on the block as per Ford Service bulletin.
Every complete motor that leaves the factory....bears a number stamped on the cylinder block ...Separate cylinder blocks do not bear a number.