Discussion in 'Trainspotter ID' started by Triplex, Oct 7, 2006.

  1. Triplex

    Triplex Active Member

    The MRS-1 (Military Road Switcher 1), built for the US Government, was actually two types of locomotive. One built by Alco and the other by EMD, they had similar specifications. Both were light 6-axle engines with variable-gauge trucks and small overall dimensions. Both of these characteristics were to permit operation overseas. Most other countries have smaller loading gauges than the USA, Canada and Mexico.

    The Alco and EMD MRS-1s are quite distinct.

    Alco MRS-1s:

    EMD MRS-1s:

    Both types of MRS-1 have high walkways. EMD MRS-1s have a peaked roofline and a fuel tank divided in two. Alco MRS-1s have a large raised grille like an early RS-series, a single rectangular fuel tank, battery boxes under the cab, and sometimes a tall stack. Handrails on both types are variable and often nonexistent.
  2. inflammable

    inflammable New Member

    At a museum that I volunteer at, we have maybe two and a quarter Alco MRS-1s. 'Two and a quarter?', you may ask? The quarter is a truck from a third one.
    The overall truck. It was kept in order to provide spare traction motors should one of the other units need a replacement.

    This is on the outside of a wheel, along the axle. Notice there seems to be a few inches of clearance between the side of the wheel, and the bearing box. This is clearance for the wheel to be moved outwards.


    At a regular locomotive maintenance facility, the wheels would be able to be pulled off the axles, shims installed, and the wheels pressed back on, in order to change the gauge of the axle.


    This is just the inside end of the entire truck. You can see the traction motor, and the electric leads. The black plastic is covering the connections for the blower air, which cools the motors.

    The intended wide gauges were the 60 inches of the former USSR, and the 66 inches of Spain and Portugal. Remember, these locomotives were designed shortly after World War 2, and before the idea of Mutually Assured Destruction further cooled the heels on either side of the Cold War. The US Army wanted to be ready for another continental invasion of Europe.

    The locomotives could have been used on a narrow gauge railroad, such as those popular in Southeast Asia, but they would have required new trucks, as the above style would only spread, not contract. At the time, the need for the narrow trucks wasn't realized, even with the Korean Conflict going on.


    Attached Files:

  3. ytter_man

    ytter_man Member

    Interesting loco, i knew the Army ordered custom switchers in steam and diesel but never knew they had heavy power like that in diesel besides normal SD's and such.

    Do tell, are the couplers quick-disconnect for the attatchment of Russian SA-3's? There looks to be plates on the pilot for the addition of buffers as well, is my assumption correct? Might need vac brakes too lol...

  4. inflammable

    inflammable New Member

    I haven't seen up close the European Chain and Buffer equipment. Ours is all normal American couplers. There is an accompanying fleet of freight cars which were also intended to be quickly placed into service during wartime, and one of these flatcars, with the European style chains, is on display at the Army Transportation Corp Museum in Virginia.

    The Knockdown Fleet of freight cars is another post all by itself. We have a couple of the boxcars at our museum, they were built in 1952 or so, but due to being outside braced, and smaller than the other equipment, everyone thinks they are from WW1 or from Europe anyway.


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