Now, about the "F8"....

Short story: there never was such a thing, but...

Longer story: Probably the most important difference, from an operating point of view, between an F3 and an F7 was that the F7 had higher capacity (D-27; F3 had D-17) traction motors. Both had 16-567B engines and D-12 main generators. (The other difference I know about is that the F7 used a different design of dynamic brake-- there's probably more, but I have never seen anything listing the changes.) A few of the last F3 units were built with the new traction motor: these were apparently referred to in some EMD documents as F5, but the designation never made it to the marketing people. (Maybe they thought the dramatic impact of the announcement of the new, 1949, line -- F7,E8,SW-7, GP-7, SW-8 -- would be lessened if they publicized a separate "model change" a few months earlier?)

Was there anything similar at the other end of F7 production? I have NEVER seen anything to suggest that anybody, in EMD or out, used "F8" to refer to a late F7 with some F9 features, but were there such units? F7/F9 hybrids?

I know a number of features characteristic of the F9 were introduced during the F7's production:
---Engine: The F7 (officially) had the 567B, but EMD went to the 567BC and even to the 567C (the engine officially characteristic of the 1954 line) before the end of 1953: I have read that at least some hood units (GP-7? SD-7?) and switchers (SW-9) got the later engine designs. I don't know about F7, but it strikes me as likely.
---Automatic as opposed to manual transition: introduced after the first F7, but early enough (1950? 1951?) that it can't really be thought of as a "transitional" F7/F9 feature.
---48" (as opposed to 36") dynamic brake fan. (Was this for a higher capacity dynamic brake, or just better cooling at the same rating?) I think the early "Diesel Spotter's Guide" gave the larger fan as an F9 spotting feature; I know I was puzzled when I first saw photos of B&O F-units with the bigger d.b. fan. The October 2006 "Model Railroader" feature on F-unit "phases" says the bigger fans started getting used on F7 "around August 1952."

The F7 set sent to the Norfolk and Western as demonstrators were "tweaked" to make a good impression. In particular, I have read that their engines were reset to deliver 1600 instead of the usual 1500hp. (Since Alco, Baldwin and FM were all advertising 1600hp units, the incentive to do this is obvious. The engine was conservatively rated at 1500hp from 16 cylinders: the 567A had gone to 100hp/cylinder in its 12-cylinder version in 1949, with the SW-7. And weren't EMD's MRS-1 units rated at 1600?)

>>>>Query: were any other late F7 shipped at higher than 1500hp ratings? Certainly if some had the (more robust) 567C engine, which gave 1750hp in the F9, it would have been tempting...

Electrical stuff. The F9 had a D12B main generator. (This from the ATSF F-unit roster in "Extra 2200 South" issue #89. I don't know anything about the sequence of EMD generator sub-models, and have no particular reason to think changes coincided with locomotive model changes....) The F9 had D-37 traction motors.

Query>>>> Did any late F7 get F9-style motors or generators?
(Frankly, knowing the N&W, I'd have been more concerned with beefing up the traction motors than the engine rating if I were sending a demonstrator for them to play with!)

Lots of interesting questions here, and I don't have any of the answers; I'm not that much of an EMD guy. But I think there is an error or misconception in the engine chronology listed. (And if I'm wrong, I'd appreciate it if someone like P. Cook or mxdata corrected me-)

I don't believe that the 567BC was an interim engine between the 567B and the 567C. My understanding of the BC is that it was a modification of the B engine, designed after the C engine was in production.

The B engines could be leakers, around the lower liner water seals. The C engine solved that problem with a cooling manifold running through the airbox and water jumpers into the side of the C cylinder liners, doing away with the lower water seals. The BC modification (or retrofit) added the water manifold to a B block engine, allowing the use of C liners and the water jumpers. The B head was retained, as the water passages matched both the top of the C liner and the B block.

Many a B engine was sent back to LaGrange and upgraded to BC standards. I suspect that a good RR shop (NYC, PRR, ATSF etc. sized ) could do the conversion as well.

If my information and/or time line is wrong, I'm sure someone will let me know. I own a CF-7 with a 16-567BC, and admit that I don't know all that much about the prime mover. I haven't put a wrench (well, a BIG wrench) on the engine yet; I'm an electrician and have worked mostly on Alcos.

EDM5970---
Certainly the conversion of a Bengine to BC standard was possible for a railroad shop. (It was, I think, one of the things that Illinois Central Gulf regularly included in their 1970s GP7-->GP8 "Paducah Rebuild" program.)

I was under the impression, from things published in the railfan literature, that there were also some "as built" BC engines.

We all know that the railfan literature is not error-free: like you, I would love to hear from someone who knows!

I've found one (I'm pretty sure there were others) source of my belief that some EMD locomotives got factory-built 567BC engines in the F7 era.

Don Strack's article on Union Pacific SW7, SW9 and TR5(*) in the March/April1995 issue of "Diesel Era" (vol.6, No.2), pp. 19-20:

"EMD ended SW7 production in January 1951, with formal production of its replacement, the SW9, having begun two months earlier, in November 1950. External design differences [...] are minor [...]. Internal changes included transition from the 12-cylinder 567B engine to the later 567BC engine."

(Nothing about 567C engines at the other end of the production run, however, even though U.P.'s last SW9 were built in November 1953.)

--

(*) Part 2 of a three-part article on U.P.s EMD switchers that appeared over three successive issues.

Allen look at the last Santa Fe F7s delivered in 11-12/53 #269LABC-280LABC, the Western Maryland's F7Bs 61B, 65B, 239B, 241B, and 243B, and Alaska F7ABA 1506-1508, Alaska FP7s 1510, 1512, 1514 all delivered in December 1953. I think that is where you are going to find your answer. The WM units were uprated to 1750 horsepower in 1964. Regular F9 production commenced January 1954 right after the last F7s were built.

EMD F9A demonstrator #975 was built 2/53. This unit was later sold as NP 7050A. This would indicate to me that the 567C was in test and modifications to the engine such as the 567BC would have at least been thought of.

All diesel production data from A J Kristopans website.

Allen, some interesting questions here, I am going to do a little research on the BC engine questions and see what I can come up with.

One factor in new model introductions was the price review cycle, at regular intervals they would look at all their pricing and make any needed changes. It helped if a new model introduction fell on the notification of price changes, since that could all be communicated to the field sales and service staff concurrently. This was noted several times in internal letters to the sales and service people in the late 1940s and early 1950s.

Regarding the decision of whether to (or not to) introduce a new "model" of locomotive, that call was made by the Sales Manager and his staff. In some cases they chose to not create a new model when engineering advanced it (the F5 is one example) and in other cases they changed engineering's recommendation for commercial reasons (the GP22 and GP30). In a lot of cases you would need to be able to talk directly with the folks who made the decisions to be able to trace what happened.

This is all just another example of the importance of finding and interviewing the people who made critical decisions in the industry while they are still available to consult with. Fortunately a few of the noted railroad museums in the US, like the Railroad Museum of Pennsylvania, have made an effort to host talks by people who worked in the locomotive building industry. It would be nice if our "national" historical groups in the US, who have chapters distributed around the country, would take an interest in this too.

SSW9389--
Thanks for the tip! Which I am not in a postion to follow up right now, but maybe if someone else is interested....

"Extra 2200 South" issue #124 has a roster of ATSF freight F-units later than FT. (The ATSF FT roster is in issue #122. Passenger F-units are in issue #126.) There is no note about differences between the late 1953 units and the earlier ones built in 199-1951: The Santa Fe apparently didn't differentiate between any of them and or the freight F3, calling all the "200 class." ... With about two exceptions, the A-units among the late 1953 ATSF F7 were rebuilt as CF-7, so some may still be in existence: no guarantee, of course, that they still have their original engines!

mxdata--
Thanks! I have no intelligent comment to make. It would probably be salutary for Railfan Historians to be reminded from time to time that locomotive model numbers are marketing tools and don't necessarily reflect divinely revealed truths about technical details! ... And I second your motion about the URGENCY of collecting "oral history" from the remaining participants.

Allen, the BC engine question turns into another very interesting story. I talked with a few of the surviving "old timers" (there are very few people left who worked at the plant in this time period). They advised that the development of the 567C spanned several years before its introduction, and the water jumper arrangement worked out so well that there were many 567BC engines built up for installation in new production (including locomotive replacement orders) toward the end of "B" crankcase production. They also advised that sometime around 1954 the parts department decided to standardize their unit exchange engine pool around the modified crankcase, so that after that time, if a customer sent in a 567A or 567B and wanted it back with the original lower liner seal arrangement, he had to specify "repair and return". If not, what came back was automatically an AC or BC type crankcase.

I stand corrected. I always though the BC was a later development, to allow railroads to upgrade older B engines (and A engines as well, it seems) to C standards as far as the water system went. Thanks for clearing up my misunderstanding-

We keep learning as we go along. Allen consistently comes up with really good questions. If he gets back to working in the US at some time I hope he ends up associated with, or as the curator of, a railroad museum. His perspective for history and events would be a major benefit to any railroad preservation activity.

https://github.com/MagnumMacKivler/RLCPT2/wiki/F18 < Try This!

And This > https://github.com/MagnumMacKivler/RLCPT2/wiki/F20

Tom

RRATSTJ--
Thank you for those links!
... EMD had extensive experience producing parallel GP and F(*) models: GP7/F7, GP9/F9. So when they updated their technology for the 1959 generation of models (GP18,GP20) they would surely have been able to "shoehorn" the new power packages into an F-style carbody... if anyone had wanted to buy it.
... One possibility (if you want to write an "alternative history" novel about railroading and the locomotive industry): the Union Pacific sent some of its F3 units to EMD to rebuild to F9 standards. (These units were later transferred to the Rock Island: the rebuild didn't include Farr-Air grids for the side vents, so they look like F3.) One can imagine a railroad with lots of F3 on its roster seeking to do something similar a few years later. (Hmmm... I wonder if anybody asked about it, and what prices EMD offered for F-rebuilds and equivalent new hood units...)
... There actually was an "18 series" F unit. The New Haven's second order of FL9 (2030-2059) were rated at 1800 hp, and I think had some other technology changes. (I'm not 100% sure I remember this correctly, so check before betting money on it...) As part of the cooling radiator system for the air compressors, the GP9 and F9 had a loop of pipe on the roof: this was eliminated on the GP18, and I think on the second-order FL9. So (refer above to the discussion of how model numbers were arrived at), New Haven's second FL9 order weren't -- but legitimately could have been -- called "FL18."

From “Diesels to Park Avenue”, by J.R. Snopek and A. La May, p.13:

“Beginning in 1959, EMD produced its then current line of GP18 and GP20 models. The second order for FL9s came with improved GP18 operating controls as well as an uprated 567D1 powerplant. There was a period of time when a thought was given to identifying 2030-2056 as FL18s since they shared many of the GP18’s improvements, but the original designation FL9 was retained.”


Perhaps EMD did not want to use “FL18” in case that promoted the notion of an F18, either as a new build or a rebuild. This, from its brochure “Now is the Time for a Giant Stride in Motive Power…” indicates what was probably EMD’s preferred option for the disposition of the existing F3 fleet:



Cheers,