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 recently unveiled 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: Will SP 9010 ever operate under its own power?
A: The locomotive currently is missing the forward Voith transmission, all Cardan drive shafts, and all truck gearing, though gears are still present on the axles. There are no radiators presently installed, and no air brake compressors or auxiliary equipment like cooling water preheaters or hydrostatic pumps for the radiator fans. There is one Dynastarter (combination starter and generator) on the rear transmission, but no shaft to connect it to the rear Maybach in order to start the motor.

Q: Is it possible?
A: Possible. The rear motor could operate through the rear transmission to power the rear truck. Needed would be four Cardan shafts, one intermediate gearbox, three axle gearboxes, and a large amount of effort. Krauss-Maffei made the gearboxes as custom parts for this locomotive only, and while we have discovered that a small number of salvaged U.S. parts may still be in operation on a unit or two of European track maintenance rail vehicles, the logistics of obtaining these parts puts the  issue out of the question for the moment.

Q: Will the locomotive be a just static display?
A: No. Restoration plans are for the locomotive to have a fully-functioning operator's station in the cab, with the ability to control a trailing locomotive for power. Multiple-unit lashups were common back in 'KM Days', so the appearance will be quite authentic.

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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