Is there any data out there comparing the EE CSVT prime mover against the ALCO 251 and the GE FDL I assume that the CSVT was close to the ALCO 251 in specific fuel economy in V12 form but had more interesting maintenance procedures and the CSVT using timing chains over the timing gears that made it a more expensive engine to maintain than the ALCO and the GE. I know the later RK’s are well thought of in marine service but when used in the BR 56/58 they were less than stellar. I wonder were the issues more to do with the loco than the prime mover itself.
On a side note, I was watching a youtube stating that Sulzer were contracted to fix the issues with the GE FDL I find that hard to believe seeing that Sulzer were developing the LVA series engines.
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Timing chains on a large diesel engine sounds like a recipe for disaster.
I suspect the CSVT’s reliability was sufficient as QR,TGR and WAGR in Australia and on the the EAR, RR in Africa and CP in Europe who also had them and they worked ok From looking at the prime movers going by what I have seen on YT the CSVT looks more complex than the Alco 251 which was a NSWGR favorite. It was interesting that the former South Australian railways started dieselisation with English Electric and then went ALCO pretty quickly once the 251 was proven so I suspect there must have been some serious economics in the ALCO’s favor and in the NSWGR case they were always of the belief that pre-super series EMD, ALCO with GE/AEI electricals offered more efficiency over EMD and EE’s control systems for loco’s under 2000hp.
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Can you post a link?
A number of Western railroads attempted replacement of 7FDL engines with Sulzer engines, but that could only remotely be considered “fixing” the 7FDL engine concerns. There was an interesting laundry list of reported problems with the replacement engines, including the expected problems with both intake and exhaust valves (especially, probably, on SP – compare the experience with the K-M diesel-hydraulics).
To my knowledge none of the Sulzer repowers in this country were successful beyond testing. It may be indicative that the four TE-70 4S rebuilds sat many years after the Sulzer engines were removed (iirc for marine use) but no further effort was made to repower or rebuild them. I confess I was surprised that the M-K rebuild of an EMD using a 6-cylinder Sulzer during the ‘fuel crisis’ years failed to thrive.
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This might be of interest for those unfamiliar with the design:
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I’m no pro at prime movers but I had an AI overview to explain it to me and this might help:
The English Electric CSVL and ALCO 251 were both very popular in their day, but the GE FDL generally had the edge in terms of horsepower and reliability, especially in the later models. The ALCO 251 was a robust engine, known for its reliability and ease of maintenance, while the CSVL, while initially competitive, had maintenance issues, particularly with its timing chains. The GE FDL was a stronger engine, and with advancements in its design, it offered even greater horsepower and reliability, making it a dominant force in the locomotive industry.
Here’s a more detailed comparison:
English Electric CSVL:
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Initially a strong competitor to the ALCO 251, it had some maintenance issues, especially with its timing chains, making it potentially more expensive to maintain. The later RK models, while well-regarded in marine service, had mixed results in locomotive applications.
ALCO 251:
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A reliable and robust engine known for its performance and ease of maintenance. It was used in a wide variety of applications, including locomotives, marine power plants, and stationary power generators.
GE FDL:
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The GE FDL engine, particularly in its later iterations, offered greater horsepower and reliability than the ALCO 251. With advancements in design, it became a dominant force in the locomotive industry.
Be very careful with AI. It tried to tell me yesterday that Sulzer had their own “FDL” engine.
I am careful and I will be, and What…
Here is that youtube that mentions how GE went to a “swiss lab” which most likely Sulzer to fix the FDL’s water leaks in the 50’s. How true this is I will defer to the experts.
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That’s interesting. I always thought the 4 smaller turbo’s was superior to ALCO’s arrangement on the 251. I always wondered did ALCO ever experiment with this arrangement in an attempt to reduce turbo lag which the 251 was famous for in Railway service.
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Several details in Tromel probably explain why a multiple-turbo, or boosted turbo, wasn’t effectively tried (and black over fueled smoke was a chronic Alco issue to the last)
http://www.turbopartsworld.com/wp-content/uploads/2018/07/Alco251DR-FC-tromel.pdf
Tromel repeatedly dings Alco corporate for building to least price, with consequences to performance, longevity, etc.
I’d agree that turbo lag should be reduced with four units, since Alco isn’t using overrunning clutch gear drive to the turbo impeller like EMD (they don’t have minimum mass-flow of scavenge air concerns on a four-stroke). It would appear that they looked into boosting acceleration of the turbocharger rotor, but did it wrongheadedly when they tried and wrote the idea off as defective. The ‘correct’ approach is to use a motor-generator with Ferguson clutch on the turbo rotor, provide correct boost for fuel rate in any notch with battery power, and salvage surplus boost from the turbine as ‘regenerative’ charging of the battery. The seeming alternative was to limit excitation until the engine comes up to notch speed and then keep excitation just off the governor adjustment when it transiently accelerates the engine.
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We know Comeng for the NSWPTC/SRA 80 class cut back the acceleration to attempt to deal with the over-fueling/lag issue with the 12 Cyl 251 C block. It makes you wonder what both English Electric and GE did with the FDL to avoid the lag/over fueling issues? Did they reduce the reactivity of the governor to minimise over fueling.
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Ge in part went to 3-slope but I think the real ‘secret’ is in the extremely slow loading that GEs are often notorious for. It is my opinion that most four-stroke diesels need to be brought to rotational speed (the acceleration, as in gas turbines, consuming a considerable amount of transient horsepower from increased MEP) before they are physically torque-loaded; this implies that a load-following governor ‘lead’ excitation rather than following it homeostatically as a Woodward governor does.
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That explains a lot namely the lower excitation rate limits fueling thus allowing the turbo to catch up so to speak.
One thing I have noticed watching YT’s of both EE’s and Alcos in operation is that the ALCO 251 in 6 cyl form once upto speed seems to hold the load better than the EE’s which always sound like they are bogging down on long grades.
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Remember that none of the excitation is under engineer control. The lower excitation does two things – the ‘stated’ one is that it produces less pollution when the engine increases speed slowly, but the more critical one is that the engine rpm can increase more readily with lower electrical load on the crankshaft, and it can use less injected fuel to do the rpm increase, and the exhaust-gas mass flow ramps up more slowly to let the turbo spin up better.
One the engine has accelerated to ‘selected notch’ rpm is where governor regulation of notch speed ‘homeostatically’ – by moving the fuel rack or modulating EFI to hold governed speed within a few rpm at most tolerance – starts to work. The catch, at least for American Alcos, is that the excitation should be reduced when the governor increases fuel to the engine… meaning that the engine has lugged down to make the governor act… when it should be modulated down enough to get the engine back up to notch speed quickly instead of chasing boost (and effectively overfueling).
The fun place to watch how GE did this in the early '70s was with the U34CH, which was a U36C equipped with HEP on the traction alternator for lightweight commuter cars. What this meant was that at station stops, the prime mover kept turning at 725rpm, so there was no need to accelerate the engine when starting the train. The engine ‘beat’ would not change, but it would get deeper and throatier and the exhaust would get that Sulzer-like chug so reminiscent of the British 71000 Pacific. Laminar orange flame would come up a couple of feet out of the stack, and the back of a 10-car train would be moving faster than 35mph or so by the time it got to you. Then for several minutes after the rear car had disappeared up the line you could hear the 725rpm exhaust reflecting off various line side features, almost like a kind of sonar. It never got old!
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The EE as shown here certainly looks more complex than the 251 thats for sure
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