Krauss-Maffei ML 4000 C'C'
SP 9011 at Enzen, August 1964
|Type and origin|
|Total produced||21 North America, 16 South America|
|AAR wheel arr.||C-C|
|Gauge||4 ft 8 1⁄2 in (1,435 mm) (USA),
1,000 mm (3 ft 3 3⁄8 in) (Brazil)
|Length||67 ft 7.625 in (20.62 m)|
|Locomotive weight||344,000 lb (156 t)|
|Prime mover||Two Maybach MD870 V16s|
|Engine type||Four stroke diesel|
|Cylinders||32 (two V16s)|
|Cylinder size||7.28 inches (18.5 cm) bore ×
7.89 inches (20.0 cm) stroke
|Transmission||Voith L830rU hydraulic|
|Maximum speed||70 mph (110 km/h)|
|Power output||3,540 hp (2,640 kW) (Germany), 3,540 hp (2,640 kW) (USA)|
|Locomotive brake||Schedule 26L air|
|Locale||North America, Brazil|
The Krauss-Maffei ML 4000 C′C′ is a diesel-hydraulic locomotive, built between 1961 and 1969 by German manufacturer Krauss-Maffei in Munich, Germany. It generated 3,540 horsepower (2,640 kW) from two Maybach V16 engines. 37 examples were built for two North American railroads and one South American railroad.
In 1959, General Motors’ Electro-Motive Division (EMD) rebuilt nine of its GP9 locomotives for the Union Pacific Railroad with pre-production examples of a new turbo-supercharging system that would raise the locomotives’ horsepower to 2000. This soon evolved into the GP20.
The Southern Pacific Railroad (who served much of the same territory as UP, a rival) took this into account, as business for SP was growing rapidly. Freight trains were getting longer and heavier, and SP had to use up to nearly 10 locomotives to power long-distance freight trains. SP's main workhorses at the time were EMD F7s and GP9s. Although SP had a small fleet of 2,400 horsepower (1,800 kW) H-24-66 "Train Master" locomotives manufactured by Fairbanks-Morse, SP found that they were found not suitable for freight service and were relegated to the San Francisco Bay Area's Peninsula Commutes.
After much research, SP decided to experiment with diesel-hydraulic locomotives and stunned the railroading industry by purchasing three 3,540 horsepower (2,640 kW) ML-4000 type locomotives from German manufacturer Krauss-Maffei. Delivered by ship and unloaded at the Port of Houston, Texas on October 31, 1961, they featured two Maybach V16 1,770 horsepower (1,320 kW) diesel engines and Voith transmissions. The Denver and Rio Grande Western Railroad also ordered three units, but found them unsuitable in mountain service, and they were sold to the SP in early 1964. Upon arrival, a special track was set up at the locomotive shops in Roseville, California just for servicing the ML-4000s.
The first order of ML-4000s are referred to as “cab units,” given that they have a fully enclosed car body, similar to that of the F-unit. Following extensive testing SP returned to Krauss-Maffei for an additional fifteen units. Delivered in 1964, they featured the same engines and transmissions but looked very different on the outside. These are referred to as “hood units” because of their hood type bodies.
SP found ML-4000s unsatisfactory in service over the Sierra Nevada mountain range, so they were relegated to service in flat territory throughout California, often paired with F7s or GP9s. The locomotives were fairly reliable, with only one recorded failure. Upon ordering the second batch of ML-4000s, SP also purchased three DH643 diesel-hydraulic locomotives from Alco.
American locomotive technology began to catch up in the late 1960s, and the operation of diesel-hydraulic locomotives, while useful, was no longer justifiable. SP and other railroads had made their horsepower needs known and American builders responded by increasing horsepower on single-engine locomotives. In 1966, SP first ordered the EMD SD40 and SD45 locomotives from EMD. These new EMD locomotives, along with the U30C and U33Cs from General Electric, quickly became the new high horsepower units of choice. In 1967, a deadline of ML-4000 cab units appeared at the Sacramento Locomotive Works. Hood units soon appeared in the deadline, and the first ML-4000s were retired in September of that year. The Pacific Locomotive Association (the organization that operates the Niles Canyon Railway) came to SP with a request of a diesel-hydraulic powered railfan passenger excursion, preferably with a ML-4000 cab unit. However, the cab units were no longer operational, so hood unit number 9120, along with a pair of EMD FP7s powered a series of railfan passenger excursions in the spring of 1967, the only time an ML-4000 was used in passenger service. On February 13, 1968, SP announced the end of its diesel-hydraulic locomotive program. By the end of the year, all ML-4000s had been retired. The trio of ALCO diesel-hydraulics fared slightly better, and were not retired until 1973.
The camera car
Before the end of 1968, all but one of the ML 4000s were scrapped at Sacramento. The survivor, number 9113 (originally numbered 9010) was converted into a "camera car" between 1968 and 1969 at the Sacramento Locomotive Works. It emerged as SPMW #1, but was later renumbered SPMW 1166 due to SP's traffic computer requiring 4 digits. In June 1969, it was finally renumbered to SP 8799. Its purpose was to record films for a computerized locomotive simulator for engineer training. The most drastic change in appearance was the locomotive's short hood (or "nose"). It was completely rebuilt to house camera equipment and heavy, thick steel was used for collision protection. The front transmission was removed to house a generator to power the camera equipment. The generator drew fuel from the locomotive's original fuel tank. The two engines and rear transmission, though disabled, remained in the engine for weight. All of the controls remained in the cab so that it could control a locomotive pushing behind it, much like a cab car is used on a commuter train. The camera car could be put on the lead of any train, but it mostly made special trips with just one locomotive behind it for power. SP 8799 was based out of SP's West Colton Yard in Southern California until it was retired in 1984.
The Brazilian ML-4000s
Estrada de Ferro Vitória a Minas of Brazil ordered 16 meter gauge units between 1966 and 1969. They were the most powerful locomotives for use in metric gauge at that time. Although they had problems with traction (they would sometimes slip on the rails, practically burning them), they stayed in service until the 1980s with the arrival of the EMD DDM45.
|Denver and Rio Grande Western Railroad||3||4001-4003||Cab units; sold to Southern Pacific 9021–9023, later SP 9103–9105|
|Southern Pacific Company||3||9000-9002||Cab units; renumbered 9100-9102|
|Southern Pacific Company||15||9003-9017||Hood units; renumbered 9106-9120|
|Estrada de Ferro Vitória a Minas (EFVM)||
SP camera car 8799 was donated to the California State Railroad Museum in Sacramento in 1986. Initially, the museum removed its nose for the purpose of having a new nose built to replicate the nose that it had while it was a locomotive as part of its plan for restoration. However, that restoration never came. It sat in outdoor storage in a very forlorn state at the Sacramento Locomotive Works until it was sold to the Pacific Locomotive Association (PLA), along with several pieces of rolling stock. They were moved by the Union Pacific Railroad in the summer of 2008 from Sacramento to their interchange with Niles Canyon Railway at Hearst in Sunol, California. The Niles Canyon Railway then transferred it to its Brightside Yard. Its restoration is now underway by volunteers of the PLA. Initial plans call for cosmetic restoration, including building a replica of the locomotive's original nose, and returning the locomotive to its original number, 9010. It will retain its cab controls so that it can be pushed by a locomotive providing power from behind. In the future, one of its two Maybach engines may be made operational.
|Wikimedia Commons has media related to Krauss-Maffei ML 4000 C'C'.|
- Operating Manual Road Locomotives Model ML4000 C'C' Diesel Hydraulic. Krauss-Maffei München.