What Year is My D4400 Power Unit?

I'm pretty sure it's a 1943 but I'm not certain. It originally came out of a Bay City crane. I bought the motor off Dean Wack. It runs but the pony needs rebuilt I had planned on putting it in my No. 10 Auto Patrol that had a junk engine but somebody cut it up when scrap was high before I got it home. I found another No. 10 Auto Patrol though that I'm trying to get to put it in that again has a bad engine. The serial number on the engine is 1S4444. What year is it and how many of this serial type did they make? Here's some pictures of it when we went to get it in the fall of 2008. Any thing would be helpful. Thanks, Josh.

My Cat SNID book says they went in production in 1936 so as high as it is 1943 sounds to be in the range of it as not many were used back then I,d think.Some on here have books on each year things were made so I,m sure someone will chime in.

My Link Belt LS50 crane has power unit 4402. No idea of what year though.


Matt

The D4400 Industrial Engine was manufactured with several serial numbers as follows:

4H0001-4H9999..........1936-1940
3R2001-3R2999...........1940-1942
1S0001-1S4999..........1942-1947
6S0001-6S0105..........1947

There was no significant design changes for the 12 year run. Caterpillar simply used up the allocated serial number blocks and had to create new ones. 1S4444 was manufactured in 1946.