Whats the difference between an RS2 and RS3?

[NDORFN]

One. Duh. Just kidding. The Chester & Lenoir (predecessor to the Caldwell County Railroad had RS2's and 3's when they got that RS11 we were talking about so when my wife gets off the computer I'm gonna do some heavy research and let you know what I find.

[NDORFN]

RS2 is 1500hp, RS3 is 1600hp. They both share the same Alco 244 prime mover. The RS3 (alledgedly) has a battery box behind the cab (haven't seen it yet though) which the RS2 doesn't. The RS3 is a smidgen longer at 55'-11", the RS2 is 55'-05". Other than that they are pretty much identical. The reason Alco released the RS3 was to keep up with FM and Baldwin who increased their 1500hp road switchers to 1600hp to get the edge over EMD's GP7 which remained at 1500hp. EMD had the last laugh though when they introduced the GP9 at 1750hp and it was all over red rover for it's competitors. As far as repaints and the like go, the only changes needed would be to the physics.

[NDORFN]

Ive got the RS3 extra pack but not currently installed. I'll have a look at them soon. There were some RS2's produced with 1600hp before they switched to RS3 production so there might even be some RS2's with battery boxes.

[philmoberg]

As a general rule for stock units, the 100HP difference has already been mentioned. In addition, the RS-2s had identical windows on both sides of the cab; the fuel tank was located underneath the cab with the fuel filler just above the cab floor level, and one or two breather vents just about floor level; the battery box was under the frame, directly ahead of the cab; and the air reservoirs were located under the frame just ahead of that with/without a long rectangular boiler water tank between them. The RS-3s typically had cab windows identical to the RS-2 on the engineer's side, but extended to the rear of the cab on the fireman's side; the battery boxes were located on top of the frame behind the cab, in either side of the short hood; there were access hatches on both sides of the cab below the cab floor; the fuel tank was relocated to the position formerly occupied by the battery box on the RS-2, and everything else from there forward was the same. I am aware of at least some cases in which units without train heat boilers (either as-built or rebuilt) the tank designed for boiler water was used for additional fuel.

As-built - if I remember what the diesel shop guys told me accurately, both models were originally built with air-cooled turbochargers, which can be spotted by the lengthwise exhaust stack. These proved unreliable, and at least most of these were rebuilt with water-cooled turbochargers easily identified by the crosswise stack. The thirty-one 1,600HP RS-2s, noted above, were built in 1949-1950, of which a couple dozen went to the SAL. I'm also aware that several railroads rebuilt the cab windows to different configurations.

[NDORFN]

Far out philmoberg, you're a walking encyclipedia of trains! Thanks for the info, I really enjoyed reading it and as you can see it's going to come in handy

[mapitts]

The turbocharger was improved as mentioned above form a Garrett ait cooled to a Garrett water cooled. Another little bit is the last 2 numbers of the prime mover number is the year the prime mover was introduced. 531 (1931), 539 (1939), 244 and so on.

[philmoberg]

Far out philmoberg, you're a walking encyclipedia of trains! ...

That very kind of you, but it's closer to the truth to say that I was in the right places at the right times - all in the space of about three years - as a generation and an era passed into history. These were a group of guys who listened patiently to a load of questions and gave very generously of their time and experience to teach anybody with the the patience to listen to their answers. I figure I owe them for that, and since most of them have passed (or I've lost track of most of those few who haven't), I guess the best I can do is pass their legacy along. They were certainly a unique bunch, and I miss their wit and wisdom.