Ruston RK270: Greatest loco engine we never had?

squizzler

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This seems to have been an engine with great unrealised potential. Although it was installed and used in prototypes, my understanding is that it had two occasions where it could have become a mainstream engine.
  • I understand that Alco offered the RK270 under its own name for a while in the 1980s but nobody ordered it. I think I have seen a scanned article from an engineering journal to announce this but cannot find it to link now.
  • Six cylinder RK270Ts were installed in a pair of class 37/9s as prototypes for an abortive class 38. The engine was also considered for the class 60 but lost out to the Mirrlees Blackstone 275. I understand that the MB275 is a heavier engine relative to the RK270.
The RK270 went on to have a very successful fast ferry career in the late 1990s. In my opinion, if it had made it into the USA, its performance could have destroyed that of native engines of the time from the likes of EMD, GE.

Along with the Sulzer 12LVA24 (I would say more so) is this an engine that never really had its chance to shine? Does anybody have more info or anecdotes to suggest what might have been? What big loco engine do you feel is most overlooked in rail history?
 
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43096

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This seems to have been an engine with great unrealised potential. Although it was installed and used in prototypes, my understanding is that it had two occasions where it could have become a mainstream engine.
  • I understand that Alco offered the RK270 under its own name for a while in the 1980s but nobody ordered it. I think I have seen a scanned article from an engineering journal to announce this but cannot find it to link now.
  • Six cylinder RK270Ts were installed in a pair of class 37/9s as prototypes for an abortive class 38. The engine was also considered for the class 60 but lost out to the Mirrlees Blackstone 275. I understand that the MB275 is a heavier engine relative to the RK270.
The RK270 went on to have a very successful fast ferry career in the late 1990s. In my opinion, if it had made it into the USA, its performance could have destroyed that of native engines of the time from the likes of EMD, GE.

Along with the Sulzer 12LVA24 (I would say more so) is this an engine that never really had its chance to shine? Does anybody have more info or anecdotes to suggest what might have been? What big loco engine do you feel is most overlooked in rail history?
Why would the two pre-eminent US loco builders of the time - GM and GE - have bought in third party engines when their own 710G and 7FDL engines were successfully operating?
 

squizzler

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I don’t know, all I’m suggesting is if a stud of RK270 powered locomotives had been put in service, they would have smashed the American designs (as far as engine capability was concerned).

The Ruston had power per cylinder that would only be reached by American builders this century. And we know it to be reliable from its prototype form in class 37/9; BR had a history of breaking engines that worked fine on other railways.
 
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Helvellyn

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What tipped the Class 60 choice towards Mirrlees then if the Ruston was so good? Just curious because it was only fitted to two locomotives as well.
 

ac6000cw

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What tipped the Class 60 choice towards Mirrlees then if the Ruston was so good? Just curious because it was only fitted to two locomotives as well.
Mostly fuel economy, as far as I remember i.e. (theoretically) lower whole-life costs.
 

randyrippley

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If you want "the greatest loco engine we never had" you need to look at some of the uprated Deltic designs to see what could have been possible.
The Deltic T18-37K (E239) was used in MTBs and generated 3,100hp - in the 1950s
By 1968 the CT18 was knocking out 4,000hp
Two would have fitted into a class 50 bodyshell giving you 8,000hp out of a 110t class loco
 

ac6000cw

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Two would have fitted into a class 50 bodyshell giving you 8,000hp out of a 110t class loco
Well the engines might have fitted, but the necessary cooling systems and sensible capacity fuel tanks they'd need certainly wouldn't have.

On the other hand a single-engined 4000hp Bo-Bo might have been interesting (a sort of stretched, diesel powered, class 86 equivalent).
 

ac6000cw

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I understand that Alco offered the RK270 under its own name for a while in the 1980s but nobody ordered it. I think I have seen a scanned article from an engineering journal to announce this but cannot find it to link now.
Alco pulled out of loco manufacturing in 1969 and subsequently sold their diesel engine business in 1970.

I suspect the association of the RK270 with the Alco name was because GEC later acquired the ex-Alco diesel engine business (quote below from the Alco history page on Wikipedia):

After the termination of locomotive production in 1969, the locomotive designs (but not the engine development rights) were transferred to the Montreal Locomotive Works, which continued their manufacture. The diesel engine business was sold to White Motor Corporation in 1970, which developed White Industrial Power.[18] In 1977 White Industrial Power was sold to the British General Electric Company (GEC) which renamed the unit Alco Power. The business was subsequently sold to the Fairbanks-Morse corporation, which continues to manufacture Alco-designed engines in addition to their own design.
 

Tynwald

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As I remember. The 2 locos designs offered for class 60. Brush product, with Mirlees MB275T (this was part of the Brush group).The GEC offer was effectivily a GM loco, built under license in the UK. GEC was convinced this is what BR wanted. Therefore the Ruston engine (part of the GEC group) never even got offered. I believe that BR really wanted the Ruston engine, above the Mirlees. But it wasn't an option.
 

ac6000cw

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Why would the two pre-eminent US loco builders of the time - GM and GE - have bought in third party engines when their own 710G and 7FDL engines were successfully operating?
I completely agree :)

I don’t know, all I’m suggesting is if a stud of RK270 powered locomotives had been put in service, they would have smashed the American designs (as far as engine capability was concerned).
There is quite a long history of foreign and other US domestic diesel engine manufacturers trying to break into the US diesel loco market.

Southern Pacific had some Maybach-powered high-power diesel-hydraulic locos for while, and also several railroads tried various Sulzer powered locos (see https://www.derbysulzers.com/usa.html ). Cat tried for years to break properly into the high-power loco market, but never managed it beyond a handful of prototypes and very small fleets e.g. the MK5000s (until they eventually bought their way in by buying EMD!).

It's not the 'mine's bigger than yours' stuff like power-per-cylinder ratings than matter to operators of locomotives - it's reliability, low servicing costs and fuel consumption that do i.e. the bottom-line financial costs of power to haul freight around.
 

randyrippley

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Well the engines might have fitted, but the necessary cooling systems and sensible capacity fuel tanks they'd need certainly wouldn't have.

On the other hand a single-engined 4000hp Bo-Bo might have been interesting (a sort of stretched, diesel powered, class 86 equivalent).

Imagine an HST with a 4000hp Deltic in each power car.............
 

43096

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There is quite a long history of foreign and other US domestic diesel engine manufacturers trying to break into the US diesel loco market.

Southern Pacific had some Maybach-powered high-power diesel-hydraulic locos for while, and also several railroads tried various Sulzer powered locos (see https://www.derbysulzers.com/usa.html ). Cat tried for years to break properly into the high-power loco market, but never managed it beyond a handful of prototypes and very small fleets e.g. the MK5000s (until they eventually bought their way in by buying EMD!).

It's not the 'mine's bigger than yours' stuff like power-per-cylinder ratings than matter to operators of locomotives - it's reliability, low servicing costs and fuel consumption that do i.e. the bottom-line financial costs of power to haul freight around.
I rather liken it to the old cliché of rock bands trying to "break America". Most fail.

Imagine an HST with a 4000hp Deltic in each power car.............
I'd rather not.
 

Strathclyder

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Southern Pacific had some Maybach-powered high-power diesel-hydraulic locos for while.
Ah, the Krauss-Maffei ML 4000.

Going OT for a sec...

The Denver & Rio Grande Western Railroad (the SP's operating partner at the time) took 3 of the 6 prototypes, but these were subsumed into SP's roster in 1964. SP would take 18 all told. They barely lasted a decade with SP before being displaced by diesel-electric machines from domestic manufacturers of equivalent or superior power output and tractive effort. One of SP's locomotives (9010) is the only survivor of the type. It hauled it's first passenger train in preservation in 2019 on the Niles Canyon Railway in Fremont, CA (video from the Ben Wang YT channel below) after a extensive restoration was completed.


As a aside, Estrada de Ferro Vitória a Minas (EFVM) of Brazil took a total of 16 metre-gauge units (4 in 1966, 12 in 1969), taking the total number of 'MLs' built to 37. These faired slightly better than their North American relatives in terms of longevity, but all were withdrawn by 1980.
 

ac6000cw

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Also off-topic, but for the diesel heads, this is a video (not mine) from inside the cab of a GE ES44 'EVO' series diesel loco running a self-load engine test - 4400hp standing still !! (the power is being dumped into the dynamic brake system and turned into heat). The engine in that loco is a V12 four-stroke, so around 380hp per cylinder.


One of SP's locomotives (9010) is the only survivor of the type. It hauled it's first passenger train in preservation in 2019 on the Niles Canyon Railway in Fremont, CA (video from the Ben Wang YT channel below) after a extensive restoration was completed.
Do you know if its actually moved under its own power yet (rather than being MU'd with another loco behind it which is actually powering the train)?

Reading the info on the restoration project website - http://sp9010.ncry.org/ - the one working engine was lifted out for rebuilding in May 2019 (which is still underway). As far as I can make out, they got to the stage of the engine driving the transmission on the one mechanically complete bogie in the shed a few years ago, but not out 'on the line'.
 
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squizzler

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Why would the two pre-eminent US loco builders of the time - GM and GE - have bought in third party engines when their own 710G and 7FDL engines were successfully operating?
It's not the 'mine's bigger than yours' stuff like power-per-cylinder ratings than matter to operators of locomotives - it's reliability, low servicing costs and fuel consumption that do i.e. the bottom-line financial costs of power to haul freight around.

Whilst the EMD 710 and GE's 7FDL might have been adequate in the 20th century, the path taken by both GE and EMD in the 21st century suggest a preference for fewer but more powerful cylinders in the engine. Whereas the mainline versions of both the engines you cite would be 16 cylinders, the GEVO (unveiled in 2003) and EMD 1010 (2015) both allow powers of around 4400hp from 12 cylinders. The Ruston RK270 could have offered that to loco builders in the 1980s.

If you want "the greatest loco engine we never had" you need to look at some of the uprated Deltic designs to see what could have been possible.
The Deltic T18-37K (E239) was used in MTBs and generated 3,100hp - in the 1950s
By 1968 the CT18 was knocking out 4,000hp

Gas turbines could have provided even more power in a smaller package. Whilst interesting, like the original Deltic these would be very specialist products only suited to specific uses rather than general traffic.
Alco pulled out of loco manufacturing in 1969 and subsequently sold their diesel engine business in 1970.

I suspect the association of the RK270 with the Alco name was because GEC later acquired the ex-Alco diesel engine business (quote below from the Alco history page on Wikipedia):
Interesting, and suggest that whilst the engine could not have been licenced by the feted American locomotive builder of that name, I may not be mistaken in thinking the RK270 was marketed as an AlCo engine.

Ah, the Krauss-Maffei ML 4000.
Thank you for an interesting diversion.

This loco had two engines which appear to be sixteen cylinders each, so 32 cylinders for 4000 hp. As this differs from contemporary US loco engines in the opposite way from the RK270, which would develop its power using fewer cylinders, I feel its failure has no bearing on how the British engine would have performed on US metals. Also that locomotive was not merely comparing a German engine to native ones, but also a whole different drive chain technology. I wonder if a loco with the same two engines but using an electric transmission would have been successful in the USA?
 
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Strathclyder

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Do you know if its actually moved under its own power yet (rather than being MU'd with another loco behind it which is actually powering the train)?

Reading the info on the restoration project website - http://sp9010.ncry.org/ - the one working engine was lifted out for rebuilding in May 2019 (which is still underway). As far as I can make out, they got to the stage of the engine driving the transmission on the one mechanically complete bogie in the shed a few years ago, but not out 'on the line'.
Don't think it has yet, as far as I can work out. Perhaps it would've been more accurate for me to say that it made it's preservation debut in 2019 at the head of a train, but not actually providing anything in way of power. The description for the video below (from the jrechiel1 YT channel) says that the GP9 behind was providing the power on that run.

 

ac6000cw

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I've managed to answer my own question - yes, it has moved under its own power, back in 2017:



...and from inside the cab:


(Note - as far as I know, the engine had no working cooling system at that time - just the water in the engine block - hence the very limited running time)

...and for the diesel heads, this is starting a 50 year-dormant V16 Maybach for the first time:


More SP 9010 restoration project videos here - https://www.youtube.com/user/critter3368/videos
 

Strathclyder

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I've managed to answer my own question - yes, it has moved under its own power, back in 2017:



...and from inside the cab:


(Note - as far as I know, the engine had no working cooling system at that time - just the water in the engine block - hence the very limited running time)

...and for the diesel heads, this is starting a 50 year-dormant V16 Maybach for the first time:


More SP 9010 restoration project videos here - https://www.youtube.com/user/critter3368/videos
Indeed, it has moved under it's own power in preservation, just not at the head of a revenue-earning train. At any rate, #9010's transformation since arriving at the Niles Canyon Railway is nothing short of remarkable considering it's now unique status; from a scrap-line resident to looking like it just rolled out of KM's factory in just over 11 years.
 

ac6000cw

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At any rate, #9010's transformation since arriving at the Niles Canyon Railway is nothing short of remarkable considering it's now unique status; from a scrap-line resident to looking like it just rolled out of KM's factory in just over 11 years.
I agree :) - it's in the 'never thought it could happen' category. The discovery that there was a set of bogies from a KM4000 underneath a soon-to-be-scrapped ballast cleaning machine in France was a major stroke of luck in particular.

Whilst the EMD 710 and GE's 7FDL might have been adequate in the 20th century, the path taken by both GE and EMD in the 21st century suggest a preference for fewer but more powerful cylinders in the engine. Whereas the mainline versions of both the engines you cite would be 16 cylinders, the GEVO (unveiled in 2003) and EMD 1010 (2015) both allow powers of around 4400hp from 12 cylinders. The Ruston RK270 could have offered that to loco builders in the 1980s.

The development of the GE/Deutz '7HDL' and the EMD 'H265' engines (effectively direct predecessors of the EVO and the 1010, respectively) was driven by a desire to market 6000hp locos - the idea being that one of those could replace 2 x SD40-2 on faster freight/intermodal services. That happened in 1995-1996 (so in the 20th century).

A mixture of troubles with both engine designs and a loss of interest in the 6000hp loco concept by railroads meant only a relatively small number of 6000hp locos - AC6000CW and SD90MAC - were ever produced.

GE (without Deutz involvement - the partnership had soured by that point due to the 7HDL troubles) then developed the EVO engine as a replacement for the 7FDL and 7HDL, including both V12 4500hp and V16 6000hp versions. (The 7FDL was at the end of its development potential, so GE needed something new to meet Tier 2 and beyond emissions rules).

EMD stayed with the V16 710 2-stroke for the SD70 series because that's what their customers wanted. Switching to the 1010J in the current SD70ACe-T4 was driven by a need to meet Tier 4 emissions requirements without using SCR (which the 710 couldn't manage economically - EMD did try though).

Pure speculation, but given that GE went into partnership with Deutz to develop the 7HDL in the early 1990s, maybe they also looked into licensing a design like the RK270 at the time - we'll never know...

In my opinion, if it had made it into the USA, its performance could have destroyed that of native engines of the time from the likes of EMD, GE.
Another factor with higher power engines & locos was that the customers of EMD, GE and Alco were not very interested in buying locos with more power than the wheelslip control systems of the time were capable of handling.

EMD offered the SD45/SD45-2 at 3600hp from 1966 onwards, but most customers preferred the 3000hp SD40/SD40-2 instead as that had a better balance of usable power, haulage capability and cost (both purchase and running costs). GE and Alco offered 3600hp models a few years later, but again they weren't very popular.

As better wheelslip control was developed, there was a steady increase in engine power offered to go with it e.g. EMD SD50 at 3500hp, SD60 at 3800hp, SD70 at 4000hp and 4300hp (all V16 engines). GE followed a similar path with the FDL engine design and their U, -7, -8, and -9 series locos.
 
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squizzler

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I found the article referred in the OP: link. There is not very much on the intended application of the engine, although the

The development of the GE/Deutz '7HDL' and the EMD 'H265' engines (effectively direct predecessors of the EVO and the 1010, respectively) was driven by a desire to market 6000hp locos - the idea being that one of those could replace 2 x SD40-2 on faster freight/intermodal services. That happened in 1995-1996 (so in the 20th century).
It may not have been that the builders envisioned the 6000hp market as the be-all and end all of their new engine designs. Certainly, it is common in other areas for new features to be introduced in a flagship product before rolling it out to the rest of the range. In this instance the high power locos seem to have been a flop, but arguably not a complete failure since it provided real world data on the designs the manufacturers would eventually need.
Another factor with higher power engines & locos was that the customers of EMD, GE and Alco were not very interested in buying locos with more power than the wheelslip control systems of the time were capable of handling.

EMD offered the SD45/SD45-2 at 3600hp from 1966 onwards, but most customers preferred the 3000hp SD40/SD40-2 instead as that had a better balance of usable power, haulage capability and cost (both purchase and running costs). GE and Alco offered 3600hp models a few years later, but again they weren't very popular.

As better wheelslip control was developed, there was a steady increase in engine power offered to go with it e.g. EMD SD50 at 3500hp, SD60 at 3800hp, SD70 at 4000hp and 4300hp (all V16 engines). GE followed a similar path with the FDL engine design and their U, -7, -8, and -9 series locos.
According to the mid Hants railway, 37905 produces 1800hp from its six cylinder Ruston. A V-12 would therefore be expected to produce 3600hp, bang in the locomotive power "sweet spot" both GE and EMD. We know that it passed BR type approval and ran successfully in a class 37 test mule, so there is no reason to think that it would have struggled to meet the demands of US railroading. Actually I think US railroading is easier because the number of cycles between idle and full load must be fewer in the big country compared to that achieved whilst scratching around a busy mixed network like the UK.

Living in Jersey, I am quite acquainted with travelling by RK270 in its fast ferry guise where the Condor Rapide, an 86m Incat wave piercer, is powered by four 20 cylinder units - 9626bhp each:o. During the blooming of high speed catamaran ferries in the 1990s, the RK270 ruled. Rapide is latest in a line of Incat products run by Condor and I recall some of the early ones (also RK270, natch) would suffer frequent engine outages (usually to do with the blower I think), but the design did come good. Ruston themselves would respond both to their success in this field and the increasing size of these craft by developing the RK280 tailored for this market but by then I think the mania for high speed ferries ended and I don't think the RK280 (now the MAN 28/33D) enjoyed the sales of the older engine.
 

ac6000cw

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Actually I think US railroading is easier because the number of cycles between idle and full load must be fewer in the big country compared to that achieved whilst scratching around a busy mixed network like the UK.
It's just different - the UK doesn't have the long, 10-15 mph mountain pass climbs that the US has e.g. it's an 80 mile climb up the west side of Donner Pass at an average gradient of 1.5%, or the long tunnels without much ventilation (where the trailing locos in a consist are sucking in the exhaust gasses from the lead locos - see the photos of a coal train emerging from a tunnel in Montana in this PDF from Trains magazine - https://trn.trains.com/~/media/import/files/pdf/3/5/8/mullan_tunnel.pdf).

Also one of my favourite 'climbing the pass drama' photos (not mine) in this post - https://www.railforums.co.uk/thread...-around-california.124024/page-4#post-2421935

To illustrate the difficulties of breaking into the US diesel loco market, it took all the technical and financial resources of (100% local) GE 20 years from around 1960 to seriously threaten the market dominance of EMD, and another 10 years or so to overtake them in market share.

It would have been madness for a foreign company to try it, outside of niche markets like passenger or electric locos (which what Siemens have done more recently, albeit powered by an American Cummins QSK95 engine).
 
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squizzler

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It's just different - the UK doesn't have the long, 10-15 mph mountain pass climbs that the US has e.g. it's an 80 mile climb up the west side of Donner Pass at an average gradient of 1.5%, or the long tunnels without much ventilation (where the trailing locos in a consist are sucking in the exhaust gasses from the lead locos - see the photos of a coal train emerging from a tunnel in Montana in this PDF from Trains magazine - https://trn.trains.com/~/media/import/files/pdf/3/5/8/mullan_tunnel.pdf).
Pretty impressive clag, like that of pictures I have seen of Soviet locos. I wonder what grade fuel they are using....
 

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To illustrate the difficulties of breaking into the US diesel loco market, it took all the technical and financial resources of (100% local) GE 20 years from around 1960 to seriously threaten the market dominance of EMD, and another 10 years or so to overtake them in market share.
Not really; from a 1960 start they had not only taken market share from No 2 builder Alco, but completely knocked them out of the market in less than 10 years. The Alco factory in Schenectady NY closed down in 1969. GE did this because they were a long-time supplier of the electrical side (so already had the national product support etc in place) but Alco were letting the side down by not keeping up on the diesel or mechanical parts side. The 1956 "new" Alco 251 diesel was really just a facelift for the prewar-designed 244 they had used.

An interesting 1960s Alco "locomotive" is the well-known pair of tracked huge crawlers that Nasa have at Cape Canaveral, which have long pulled the Space Shuttle, and before that the moon rockets, around the site. They each have 3,000 hp Alco 251 engines and GE electric transmission inside. I gather the controls look a bit familiar too. They were built by a dragline excavator company which did things of that size and used Alco parts.

Pretty impressive clag, like that of pictures I have seen of Soviet locos. I wonder what grade fuel they are using....
That tunnel is at 9,500 feet elevation. Any diesel is going to have less-than-perfect combustion at that altitude.
 

ac6000cw

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That tunnel is at 9,500 feet elevation. Any diesel is going to have less-than-perfect combustion at that altitude.
It's not just (or even mostly) the altitude - Tunnel 5 on Tehachapi Pass (at only about 2000 feet elevation) is well known for causing 'combustion problems' with multiple diesels:


...and some of those locos are EMD SD40-2T/SD45-2T 'Tunnel Motors' (as they came to be known) with the engine air intakes moved down to near frame level to minimise the problem of sucking in hot exhaust gasses at roof level inside tunnels and snowsheds. Modern locos with computerised fuel injection etc. probably reduce the problem/effect, but it still happens to some extent - I've seen it with my own eyes at Tunnel 5.

Not really; from a 1960 start they had not only taken market share from No 2 builder Alco, but completely knocked them out of the market in less than 10 years.
Yes, I'm aware of that, but GE didn't outsell EMD until the mid-1980's (I've seen 1983 and 1987 quoted in articles). I was a bit out suggesting 1990 for that... :oops:

Personally, I don't think GE had a significantly better product than EMD until it introduced the Dash-8 series locos in the early 1980's, and then they romped away - in sales terms - with the successor Dash-9/AC4400 series. The late '70s Dash-7 series were probably comparable to the EMD SD40-2/GP40-2 series in performance, but the EMD product outsold them by about 4 to 1...
 

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GM overall as an organisation were very good at dominating a market, they had the ability to identify just what it was that made buyers favour them, not technology front runners, but reliability, product support, no extra charge for custom railroad paint, etc. Their buses in the USA were the same, they dominated the market for decades, but like with locomotives in the last generation they lost it all. I get the feeling the pinnacle of their success was the SD40-2. They sold a lot of F-units and GP9s in the dieselisation days which had a range of mechanical nuisances which required regular attention (like the 567B engine water leak issue, that went on for a decade), but somehow didn't impact reliability or regard.

The Tunnel Motors look a simple change on the outside but required a considerable rearrangement of equipment under the hood. I have wondered why the approach was not done for all production, did it have any downsides?
 

ac6000cw

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I get the feeling the pinnacle of their success was the SD40-2.
Probably, although the SD70 series have been pretty good (over 5000 sold to date since 1992 - UP's order for 1000 SD70M was the largest loco order in US history at the time - and from what I've read they seem to be pretty solid locos in both DC and AC drive versions).

The Tunnel Motors look a simple change on the outside but required a considerable rearrangement of equipment under the hood. I have wondered why the approach was not done for all production, did it have any downsides?
I've wondered that too on occasion - I suspect the main downside might be that the air down at frame level is dustier, particularly for the trailing locos in a consist e.g. dust from the sanders and surface dust/powdered snow blown around around the air turbulence at higher speeds. Filters can deal with that, but it might mean they needed more maintenance.

Certainly since the 'Tunnel Motor' deliveries finished (which only Southern Pacific and DRGW ordered), SP subsequently appeared to buy only 'standard' locos from both GE and EMD.
 

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