Southern Pacific 9010
The FAQ Page

K-M Kwickies

FAQ's about SP 9010

Q: How do you pronounce "Krauss-Maffei"?
A: Pretty easy. Krauss sounds like 'house'. For Maffei, some say 'mah-FYE', while most say 'MAH-fye'.

Q: What is a Diesel-Hydraulic?
A: To transmit power from the Diesel motors to the wheels, SP 9010 has 'automatic' transmissions, universal drive shafts, and geared axles. Most American locomotives use generators and electric motors to accomplish the same tasks.  On a KM, the numerous propelling shafts are called "Cardan" shafts after their inventor Gerolamo Cardano who theorized such devices in 1545.  No fooling!

Q: Why did the Southern Pacific buy German locomotives?
A: In the 1960's, Germany was producing the most powerful single-unit diesel locomotives in the world, with the highest ratings for traction. SP's pioneering diesel fleet was aging and the railroad wanted fewer locomotives to haul more tonnage while also looking to reduce costs.  At the time, the Germans had a convincing sales case for efficiency, power and reliability.

Q: Weren't these locomotives a complete failure?
A:  Yes and no. They were not reordered, and all were scrapped after four to six years on the job. Crews did not like their unfamiliarity. But U.S. manufacturers almost immediately began designing more powerful locomotives for sale to the Southern Pacific, with better control over traction. This may have been in part a result of the K-M 'challenge'.

Q: How different were the Diesel prime movers from U.S. designs?
A: Very. The Maybach MD870 ran and idled faster, had twin turbochargers, overhead camshafts, roller bearing crankshafts, six valves per cylinder, and was much smaller physically. You can think of the small-displacement European car engines of the 1960's as compared with big-block U.S. V-8's of the same era.

Q: Didn't these Maybachs fail in service?
A: Unlike many US manufacturers, KM was commercially and politically reliant upon suppliers for fundamental components of their product.  The Diesel engines in U.S. KM's pushed the performance envelope, while being outside KM's direct engineering responsibility.  There were faulty fuel injectors, problems with valve trains, and serious cooling and combustion problems in the tight confines of high-altitude tunnels. They were also comparatively complex for U.S. crews to work on. The same design also experienced similar problems in Brazil. Those problems were largely corrected over time by Maybach engineers, but by then, the railroads had decided to cancel the "experiment" and retire the KM's.

Q: Is this the same Maybach that now makes ultra-luxury cars?
A: The same family tree.  Once upon a time they made motors for Zeppelin airships. They are a historic branch of Daimler-Benz AG, which makes Mercedes-Benz vehicles and recently reserected the Maybach auto brand.  Maybach Motorenbau, the maker of SP 9010's two V-16 motors, now operates as MTU Friedrichshafen, and still manufactures high-output Diesel motors for rail and marine service.  
The MD870 becaume the MTU 538, and variations up to 20 cylinders continue to provide rail and marine service worldwide.

Q: How do you pronounce "Maybach"?
A: English-speaking folks can say 'MY-bock' and pretty much get by with that. Europeans add the 'ch' sound, formed between the back of the tongue and the hard palate.. Don't try this at home without adult supervision.

Q: Does anyone still make Diesel-Hydraulic locomotives?
A: Yes. The same company, Voith Turbo, which made the transmissions for SP 9010, has offered a 5000HP Diesel-Hydraulic model (one of several new ventures for Voith into the building of complete locomotives), and the Voith hydraulic transmission remains a popular worldwide alternative to electric propulsion.   Krauss-Maffei locomotive building is now under Siemens Transportation Systems, but they no longer catalog Diesel-hydraulic propulsion.  The former MaK is the only other producer in Germany of D-H power, building under the Vossloh name.  There are currently no mainline Diesel-Hydraulic locomotives in U.S. service.

Q: Can SP 9010 run under its own power?
A: Yes, it can… and it has. 
Since February of 2017, we have successfully revived and run the rear Maybach V-16 motor, and used it to test the completely replaced, restored or revived Behr cooling system, our rear Voith transmission, and our rebuilt and geared KM Series Unit truck obtained in salvage from France. That truck was originally installed under SP 9007 (a sister to SP 9010), and was salvaged from the U.S. and shipped to Germany. There, it was installed under a 1970-model Plasser & Theurer heavy-duty rail ballast cleaner. Ultimately used in France for nearly 40 years, its long service life helped to make French rail roadbeds smooth as glass. It was rebuilt by Colas Rail, then retired. We were fortunate to be made aware of this through our extensive European contacts and supporters, and to receive substantial private donations, both large and small, towards its recovery.

Q: When will SP 9010 run again?
A: As of May, 2019 the rear Maybach has been removed and placed on a shop cradle, where it will be rebuilt using original and new parts and tooling supplied by Maybach successor MTU. The schedule for this is under development, with time, volunteers, and unforeseen mechanical circumstances or discoveries being critical factors. But we want to see this completed as soon as practical and possible.

Q: Why not rebuild the front Maybach too?
A: We receive many questions about rebuilding the forward Maybach V-16. (SP 9010 has two, so many folks suggest it’s just as easy to do two for the price of one.) 

It’s not that simple. The locomotive currently is missing the forward Voith transmission, all forward Cardan drive shafts, and all forward truck gearing, though very rusted gears are still present on the axles. There are no radiators presently installed for that power plant, and there are no radiator fans. All of these parts were custom-made for the KM USA Series Units, and would cost literally millions of dollars to re-create. In short, it would take an outsized and heroic effort to rebuild the forward motor, and secure the full complement of other equipment necessary for it to power SP 9010. 

Q: Why not raise the money and do it anyway?
A: With a fully restored and working rear powertrain, there is no operational, historic, or museum operational need whatsoever to do that. It is not in the plans, now or for the future.

Q: Is it possible?
A: Anything is possible. (See: Restoration of SP 9010)

Q: But is it likely?
A: Feel free to ask us again -- when humans are walking on the surface of Mars. Donations gratefully accepted for everything else in the meantime! (See home page for donation link here).

Q: Why is this locomotive important to preserve?
A: Historically, the ML4000C'C'  represents several significant things:
- First imported mainline Diesel locomotive in U.S. history
- World's most powerful six-axle locomotive when new
- First U.S. mainline Diesel-Hydraulic locomotive
- Strongly identified with Southern Pacific Railroad image and lore
- Stimulus for next generation of high-horsepower road locomotives
- Was camera platform for world's first fixed-base full-motion Locomotive Simulator

Q: Did SP 9010 have a nickname?
A: The Krauss-Maffei locomotives - for obvious reasons - were often called "Krauts" by Americans. Germans called them "Amerika-loks", sometimes shortened to "Amilok" or just "Ami". American crews often used other nicknames, and we refer you to the X-rated "Dictionary of American Slang."

Q: Do I have speak German to understand SP 9010?
A: Nein.

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