Help with Fairbanks Morse builders plates

I am trying to find the Engine numbers and confirm ownership of Fairbanks Morise H10-44 and H12-44 engines that the B&O owned. I have what I beleive to be six builders plates from them and am trying to confirm that they belonged to the B&O Railroad. The serial numbers are as follows (10L-143 dated 5-1949) not sure about this one but it is dark blue and was obtained at the same time as the rest saturday May 28, 2005 in Palmara Indiana estate auction. The others are (12L-719 dated 2-1953),(12L-720 Dated 3-1953),(12L-406 Dated 1-1951),(12L-405 Dated 1-1951),(12L-402 Dated 3-1951) The All Time Roster I checked only showed three H12-44s in 1951. Engine numbers 9711,9715 and 9718 This may account for all of them? If they are infact plates off B&O Locomotives. All Plates are dark blue with three showing yellow paint at the edges as with the B&O Strip of the time. I am looking for the engine numbers to go with them if they can be confirmed as belonging to the B&O.

Many thanks to all that have read this post and to anyone that can help out or point me in the right direction. I have already contacted the B&O Historical Society.

I have since learned that the B&O purchased 9 H12-44s In 1951. So here would be three of them. If they are infact from the B&O.

None of your builder numbers seem to match any of B&O's H10 or H12 switchers. The closest were B&O 9718-19, which had b.n.'s 12L400 and 12L401, built 3/51 -- but the series then jumped to 12L774 for 9720, built 9/53.

Well that acounts for two of them in 1951. What about the other seven. 12L-402 also built 3-1951 same as your 12L401 number is. the next numbers in the series I have are 12L-405 and 12L-406 that were built 1-1951 I know that seems out of order but I have not found the Fairbanks Morse serial numbers to be in any kind of order. Such as 1,2,3,4,5 they seem to jump all over the place from my research.
I show a purchase of 9 locos by the B&O in 1951 acording to the all time roster http://www.northeast.railfan.net/bo2.html it says that they were engines 9710 to 9719 You show number for 9718 and 9719 which would sugest that they were the last delivered yet they have lower serial numbers as if to sugest that Fairbanks Morse counted down the order when building rather tha counting up. Lets say the first out of the shop were the high serial numbers as looks to be the case.
Lets ponder that Fairbanks morse may have started with 12L-409 on the order and counted them down as completed or delivered. That would make all of them B&O Number?

Now onto the 1953 builds I Note two separate puchases on the all time roster Look again at the serial numbers. You give me 12L774 which is in the first two puchased as Engines 9720 and 9721 I have number 12l-719 and 12L-720 out of the second puchase lot which which if the serials are going down based on completion date is correct they very well could be B&O Plates from the second order group

A Recap! Lets just look at the serials and build dates on the 1951 plates I have vs the dates and numbers you show. They are going in reverse of each other! Now let say the Locomotive numbers were assigned as delivered to the B&O The high number Locos having 9719 and 1918 with the lower serial numbers of 12L-400 and 12L-401 and it also suports this most likely fact.

I Thank You very much for the info as I am even more sure that they are most likely B&O numbers due to the close prox. of the serials.
May I ask where you found the info? As I have seveal hours in research with out much luck on B&O Serial numbers.

Let's go back and take it from the top: None of your plates are B&O plates -- at least to the best of my knowledge.

Following is B&O's roster of H10s and H12s, with builder numbers. As you doubtless know, the 9700-series numbers date to 1956 when B&O went through a massive renumbering program. Pre-1956 numbers are shown in parentheses, where applicable:

H10-44:

9700-9709 (300-309) -- 12L86 through 12L95 in order, 12/48-1/49

H12-44:

9710-9719 (310-319) -- 12L392 through 12L401 in order; all 3/51 ex. 9710, 2/51

9720-9721 (196-197) -- 12L774- 12L775, both 9/53

9722-9726 -- 12L1089 through 12L1093 in order, all 5/57

This data is from James Mischke's "Baltimore and Ohio Diesel Locomotive Roster," 1998 (first) edition. I think he's reprinted it several times since then with updates, but this basic data should be the same.

Unfortunately, I don't have a full F-M builder list, so I can't help further. One possibility is Milwaukee Road; another might be PRR.

Ok the problem is solved They all belonged to the K&I Kentucky and Indiana Terminal Railway. Engines #57,60,63,64,65and 66. Here is where I found the information http://www.thedieselshop.us/KIT.HTML Many Thanks To all as I tried to sort this out. The most likely reason for number Colors so close to the B&O along with the B&O serial Number 12L-402 being so close to B&Os 12L-401 is most likely because the B&O Owned a portion of the line along with the monon and southern Railroad.

Thanks To all!
Jeff