Will SCR/DEF bring back the EMD 710 .

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Posted by YoHo1975 on Monday, September 4, 2023 11:27 PM

Well EMD will gladly sell you and SD40J too. It's not clear to me if the SD70J either the 6 axle or the 8 axle can only be a new frame or not.


I think Overmod has the gist of it. Engines are going into storage. It was a oneoff and at least out west here, don't know about NS, Battery locomotives are what's being looked at.


And then there's hydrogen which is also being looked at. 

Unless a T4 710 ALSO reduced CO2 emissions. Which of course, it can't since that's the fundamental output of a carbon consuming combustion engine. It's unlikely there will be a huge market.

As noted though, if T5 comes around and DEF is mandated, well, maybe then we'll see a bunch of ACes and SD70Ms going in for DEF additions. 


But I also think we'll se more Hydrogen, more Batteries and perhaps even some catenary go up.


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Posted by blue streak 1 on Monday, September 4, 2023 10:44 PM

Still have to wonder with the many locos with intact frames become electrification units with AC traction.  Or they might become some kind of hybrid and operate with a diesel s  That would be a set up similar to the ALC42Es that run on diesel say on flatlands and E mode on grades?

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Posted by BDA on Monday, September 4, 2023 6:05 PM

Are there still hundreds of potential rebuilds sitting around or are they drying up .

I suppose some sort of incentive scheme for the DEF is a lot to hope for .

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Posted by SD70Dude on Sunday, September 3, 2023 2:46 PM

The Tier-IV compliant 710 with an aftertreatment system has been available for marine and stationary use for several years under the E23B name.

This article has a shot of a towboat engine room:

Since it seems to be accepted that there will eventually be an EPA Tier V that will most likely kill off any remaining non-DEF engines, it will be very interesting to see the responses to it.  Will the manufacturers and railroads bite the bullet and turn to DEF, will alternate fuels like natural gas or hydrogen become more common, will we start seeing mainline electrifications, or will everyone just continue exploiting loopholes and rebuilding older diesels to Tier-III or less?  

Greetings from Alberta

-an Articulate Malcontent

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Posted by Overmod on Sunday, September 3, 2023 8:00 AM

I'm curious to know why it's stored.

It requires DEF to operate, and due to the way SCR/DEF was mandated in the United States, the engine controller is required to (as the charming euphemism says) "derate the engine to zero" when the DEF runs out.  That's a poor proposition for road operation when there are many non-DEF locomotives already 'mothballed'.

Remember that the testing in the mid-2010s only left the NOx emissions noncompliant by a fraction of a percent over about 3% of the test duty cycle.  That is not a really significant addition to nitrogen-oxide emission especially given the dramatic reduction in atmospheric HC.

In any case, the entire premise of the locomotive has had the pins kicked out from under it by the development emphasis on zero-carbon.  The tech alternatives all lack the characteristics that make catalytic reduction of NO/NO2 necessary in the first place.

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Posted by BDA on Sunday, September 3, 2023 3:37 AM

I'm curious to know why its stored .

Hopefully it was not just a promo mule .

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Posted by JayBee on Friday, September 1, 2023 9:33 PM

Here is a link to a photo of the lcomotive on Chris Toth's website.

NS GP34ECO 4800

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Will SCR/DEF bring back the EMD 710 .
Posted by BDA on Friday, September 1, 2023 7:22 PM

I was reading an article recently about an Eco rebuild that had a GP unit with a Tier 4 approved 710 in it .

I can see a day when SCR and DEF will be unavoidable and if thats the case Operators may prefer this on a 710 rather than the 1010J .

Presently rebuilding older power to Tier 2 or 3 standards is the cheaper easier option but the day will come when its not possible to do this .

Thoughts ?




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