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  • GP/MP15T?

  • Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.
Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.

Moderator: GOLDEN-ARM

 #98042  by AlcoMD
 
Anyone know the rationale behind the application of an 8 cylinder turbocharged 645 engine in leiu of the 12-645 normally aspirated variety in the GP/MP 15T ?

Did the fixed and variable costs associated with the turbo square with the fixed and variable costs of four less power assemblies, smaller block, etc ?

Neither Alco or GE sold a whole lot of locos with an V-8 turbocharged engine.

 #98072  by Justin B
 
The rationalle is the same as the one found in the 38/39 series of locomotive. The turbo is not necessarily a high maintence item as long as the prime mover spends enough time in the upper notches to keep it from running off of the clutch. If a railroad figured that it could work the engine hard enough to justify the turbo, then they would spec that and reap the rewards of far more efficient operation. If an engine was to spend most of its life putting around in the lower notches then there really isnt a justification of a turbo.

 #98153  by AlcoMD
 
huh ?

My point is that switching locomotives usually don't spend a lot of time operating in the high notches. In fact, the constant notch excursions characteristic of switching activity would seem to be the type of application for a N/A engine-not a geared EMD turbo.
 #98262  by SD Shortline
 
The MP(multi-purpose) 15T was intended to be one step up from a yard goat, more like a GP. Although, the small switcher cabs they had were unsuitable for most mainline activities. There were not a great deal of MP locomotives built, Turbo'd or blown either way.

I believe the CSX and LIRR units were used in local service, but the LIRR locomotives are designed with passenger service in mind. RR's probably couldn't justify the added expense of the MP's over a SW1500 which for the most part is just as capable.

If the MP/GP15T's were out on the main, they would probably be hoofing it to begin with. So they would be benifitting from the turbo. Also, some GP15T's had dynamic braking. I thought I read somewhere that the dynamics got in the way of the exhaust system on the 12-cylinder engine but the 8T worked OK.

 #101957  by soo6617
 
AlcoMD wrote:huh ?

My point is that switching locomotives usually don't spend a lot of time operating in the high notches. In fact, the constant notch excursions characteristic of switching activity would seem to be the type of application for a N/A engine-not a geared EMD turbo.
Nothing says that a railroad has to make a smart decision. SBD and one industrial customer were the only purchasers of the MP15T, the railroad must have thought that it was a more economical way to go. Only they know whether they were right or not. It must be noted that most Alco switchers were built with turbos, as are many industrial type switchers.

 #102865  by ACLfan
 
Well, regarding Seaboard System's MP15T units----CSX hasn't retired them, dumped them, or parked them off in some out-of-way place----and they are still in active service.

So, that must say something about CSX's assessment of their performance.

ACLfan