A Guide to the U23B

[danraitz]

U23B
Dates Built:  August 1968 to June 1977
Number Built: 481

Main spotting feature between the U23B and the U30B is in the number of tall engine compartment doors.  Because the U23Bs were equipped with V-12 prime movers, there were only six such doors per hood side. Whereas, on the V-16 prime mover of the U30B there were eight tall doors per side.

Here is a breakdown of different phases and their spotting features. 

     phase I,   a: Entire hood below the radiator is the same width as the radiator itself.

                    b: A flat wire mesh covers the equipment air intake and radiator grilles.

                    c: Flaring on top of hood in front of radiator bulge.

                    d: Built up area on pilot.

                    e: Headlight casing is rectangular.

                    f: Half length handrail notch in stepwells.

                       Dates Built: Aug. to Sept. 1968
                       # Built:         16 (D&H #301 - 316)




Here is a shot showing the flat wire mesh.






    Phase IIa: * The flaring disappears from the roof top.
                   * The intake screens become corrugated and project slightly out from the hood sides.

                       Dates Built:  Sept. 1969 to April 1970
                       # Built: 38. (C&O, #2300 - 2329)
                                       (Monon #601 - 608, to L&N #2700 - 2707)


 



   Phase IIb:  * Built up area of pilots disappears.

                      Dates Built:  June 1970 to Feb. 1971
                      # Built:       49 (ATSF #6300 - 6349)




     Phase IIc:  * Handrail notch in step-wells becomes full length.
      
                        Dates Built: May 1972 to May 1974
                        # Built:       100 (PC #2700 - 2749)
                                               (Southern #3900 - 3934)
                                               (WP #2251 - 2265)




     Phase IId: * Headlight casing becomes oval shaped.

                        Dates Built: Jan. 1973 to Nov. 1974
                        # Built:       118 (L&N #2708 - 2772)
                                               (MILW #4800 - 4804)
                                               (MKT #350 -352)*
                                               (MP #668 - 674 & #2257 - 2267)
                                               (PC #2750 - 2776)

                         * MKT units were built with short handrail notches, but otherwise are identical to phase IId's.




     Phase III: * The door latches become square and centered on the hood doors.

                       Dates Built: Dec. 1974 to June 1977
                        # Built.       160  (LV #501 to 512)
                                                 (L&N #2800 - 2824)
                                                 (NdeM #9100 - 9129)
                                                 (MP #2268 - 2288)
                                                 (SPC #40 - 46 & #50 - 59) export to Peru
                                                 (Texas Utilties #103)
                                                (Southern #3935 - 3969)
                                                (FCP #537 - 546)
                                                (Conrail #2789 - 2798)

[nsc39d8]

Dan,

I really enjoy these tutorials on the GE Universal series. Two things, first I see are the changes in the location of the small rectangular grill under the radiator. On the Southern units I model the high location was due to them having oil bath filters for air filtration latter units with the lower location were paper filters. Second, all Southern's units were built with high short hoods.

[danraitz]

One thing that I noticed while doing this research, was that there were 3 railroads that had U23Bs with a larger bottom step.
They were the Santa Fe (all units), the MKT (all units) and the Southern (first 3 orders #3900 -3934).

[hotshot3305]

Dan, here is a good side shot of the ex-Southern U23-B 3911 front steps to add to your U23 study.

[nsc39d8]

Dan,

Thanks for the step info! I have not realized this before.
Nice pic, Bob, now I got to pull both my U23's and modify them.

Dan, also I have noticed as is very evident in Bob's photo, Southern also opted for the sill cutout lift tab on their GE's, no cutout in the pilot. This includes all Universal series B and C trucks and all Dash 7's. I see that Missouri Pacific opted for the same on their U23Bs.

[danraitz]

U23B models available:

    phase I:       N scale:     None
                       HO scale:  None

    phase IIa:   N  scale:    None    
                      HO scale:   None

    phase IIb:  N scale:     None                            
                      HO scale:  None

    phase IIc:  N scale:    Atlas & Hallmark Models Inc.
                     HO scale:  Atlas & Oriental Limited

    phase IId:  N scale:   Atlas & Hallmark Models Inc.
                     HO scale: Atlas & Oriental Limited

    phase III:  N scale:   None
                     HO scale: None

Notes: Oriental Limited did ones with both low & high noses and both AAR type "B" and FB2 trucks.
           The high nose version was only available with the AAR trucks through.

           The Hallmark models came with both retangular and oval headlight casings.

[Milwaukee Road 513]

Very informative!