Monticello MRyM acquires C&IM RS1325 #31 and IT SW1200 #784

Chris Webster · **Joined:** Sat Aug 25, 2007 12:45 am **Posts:** 1090

Quote:

Monticello Railway Museum Adds Two Historic Locomotives to Collection!

Today the Monticello Railway Museum (MRM) announced the acquisition of two new diesel-electric locomotives: Chicago & Illinois Midland Railroad RS1325 #31 and Illinois Terminal Railroad SW1200 #784. Both of these historically significant engines and their respective railroads have strong ties to Central Illinois. Their preservation is key to furthering the Monticello Railway Museum’s mission of interpreting the region’s rich railroad history.

Chicago & Illinois Midland #31 is one of only two RS1325’s ever built by Electro-Motive Diesel (EMD). A unique design of a light road switcher, the RS1325 combined design elements of both EMD’s GP-series road locomotives and their SW-series switching locomotives. The #31 worked for the Chicago & Illinois Midland Railroad from 1960 until 1996, when the C&IM was acquired by Genesee & Wyoming Inc. and became the Illinois Midland Railroad. The unit was retired after 60 years of freight service in Central Illinois in 2020 before being purchased by MRM. Once delivered to the museum, it will soon be added to the rotation of operating locomotives used on MRM’s historic passenger train rides. As time and funding allows, it will eventually be restored to the C&IM’s classic green paint scheme.

Illinois Terminal #784 is one of twelve SW1200 switch locomotives delivered to the Illinois Terminal Railroad. Built in December 1955, #784 operated throughout Central Illinois, including on the same trackage currently used by MRM’s passenger trains. The Illinois Terminal renumbered #784 as #1210 later in its service life, before later serving with both the Norfolk & Western and Norfolk Southern Railways. It was retired in 1994 and sold to the Sequatchie Valley Railroad, where it worked in short line service before being acquired by Knoxville Locomotive Works. Acquired in a parts trade with Knoxville Locomotive Works, it will only be the second Illinois Terminal diesel locomotive to be preserved. The engine will undergo a mechanical and cosmetic restoration as funding permits before joining MRM’s operating fleet.

Donations to assist with the restoration of these historic locomotives can be made via GoFundMe https://gf.me/u/y8pys9 or mailed to: Monticello Railway Museum, P.O. Box #401, Monticello, IL. The Monticello Railway Museum is an all-volunteer 501(c)(3) non-profit organization, dedicated to preserving and interpreting the history of railroading.

Monticello Railway Museum would like to extend its gratitude to a number of organizations involved in these acquisitions including LTEX Rail, Illinois Midland Railway, Sequatchie Valley Railroad, Knoxville Locomotive Works, and many others.

nedsn3 · **Posted:** Sat Nov 14, 2020 2:04 pm

ex- IT #1750 is currently #3 on the Elk River Railroad in central West-by-God VA.

PMC · **Joined:** Sat Oct 17, 2015 5:55 pm **Posts:** 2877

https://trn.trains.com/news/news-wire/2 ... nal-sw1200
I wonder what that coiled pipe next to the fuel/air tanks on the SW1200 is/was, I know some high RPM units (e.g., SP 9010) used a design like that to cool the air out of the compressor, but I wouldn't think that would be an issue with a 900 RPM EMD.

Lincoln Penn · **Joined:** Wed Feb 02, 2011 9:40 pm **Posts:** 841

PMC wrote:

https://trn.trains.com/news/news-wire/2020/11/14-monticello-railway-museum-acquires-illinois--midland-rs1325-illinois-terminal-sw1200
I wonder what that coiled pipe next to the fuel/air tanks on the SW1200 is/was, I know some high RPM units (e.g., SP 9010) used a design like that to cool the air out of the compressor, but I wouldn't think that would be an issue with a 900 RPM EMD.

Uhhh......You think there is actually a difference in the temperature of the compressed air produced by a diesel locomotive based on engine RPM?

Why?

PMC · **Joined:** Sat Oct 17, 2015 5:55 pm **Posts:** 2877

Mostly from the discussion of the issue on the SP 9010 website. One of the problems that the KM's apparently had was that the original US Westinghouse compressor was made to operate at 900 RPMs but the Maybach engine could operate as fast as 1500 RPMs (that is where the 2000hp came from, and ultimately what caused them to fail fast). K-M tried to deal with this problem in several ways, the first was a series of belts and pulleys, and later a gearbox, to reduce the RPMs, the other was rooftop mounted cooling pipes. I will see if I can find the discussion of the the need for the pipes in the first place, but here is a discussion of their return to the roof (SP removed them when 9010 was converted to an unpowered camera car): http://sp9010.ncry.org/otherbody4.htm

joe6167 · **Posted:** Sat Nov 14, 2020 9:56 pm

Even steam locomotives had sections of cooling pipe between the compressor and the air reservoir...

Scranton Yard · **Joined:** Thu Feb 27, 2014 10:08 am **Posts:** 734

One great thing about the IT acquisition is that it was initiated by and is being managed by a group of three or four guys in their mid twenties. The people that run Monticello really do a great job in so many areas, including providing a supportive environment for younger volunteers. A first class operation all the way. Congratulations.

Lincoln Penn · **Joined:** Wed Feb 02, 2011 9:40 pm **Posts:** 841

Back to air compressors, before it gets completely lost:

Depending on the rules of the particular railroad involved, air compresers are supposed to be set up to start pumping when the main reservoir pressure is either 120 or 130 pounds.
They are set up to stop pumping at either 130 or 140 pounds. Air temperature of the compressed air is not even mentioned, as it doesn't matter.

On diesel locomotives where the air compressor is driven by the engine, the pump keeps turning no matter what the engine speed. Whether or not it is pumping air is determined by the settings noted above. Above the high-pressure setting, the pump is "unloaded", meaning it's still turning but it isn't pumping anything.

On newer locomotives (and electrics), the air pump is driven by an electric motor. The motor and pump turn on when the air is below the bottom pressure setting and keeps pumping until the top pressure setting is achieved, wherein the pump shuts off. Again, no mention of air temperature as it is meaningless in this use.

Locomotives all have at least some piping between the pump and reservoirs. You may not be able to see it, but it is there, somewhere. Even steam locomotives did. This is to help get the condensation out of the compressed air before it enters the rest of the system.

That 900 rpm locomotive can make as much air as a 4500 hp locomotive (assuming the compressors have the same cfm pumping capacity).

JoshSnitkoff · **Joined:** Sat May 23, 2020 9:04 am **Posts:** 3

The Port of Albany RR (NY) used to have switchers set up similarly with the piping for the air.

https://upload.wikimedia.org/wikipedia/commons/2/2b/Terminal_Railroads%2CAlbany_Port_Railroad.jpg

EWrice · **Joined:** Wed Jan 15, 2014 9:14 am **Posts:** 367

The SW9 I work on has a very similar "aftercooler" pipe arrangement but is laid horizontal above the air tank. This IT sw1200 looks like it has an oversized fuel tank that pushed the air tank up tight to the frame requiring the cooler to be moved outboard of the air tank. Good looking units, good for them for the acquisition.

CCDW · **Joined:** Wed Jan 28, 2009 4:30 pm **Posts:** 211

Lincoln Penn writes "Air temperature of the compressed air is not even mentioned, as it doesn't matter."

Actually if you read the installation instructions that cover air pumps you will find that a specific length of pipe is required between the pump and the reservoir and a second specific length between the first and second reservoir, if used, for cooling. 26 feet is the recommended length for a 9-1/2" pump and 30' for a compound. I have seen an air pump that ran low on oil on the air side and it got hot enough to blister the paint on the air side of the pump. You compress air, it gets hot.

Overmod · **Joined:** Thu May 24, 2012 1:37 pm **Posts:** 2492

I'd thought the 'aftercooling' was not because the air got hot, but because when it was that hot it contained more moisture that would get into the reservoirs.

The coil of pipe probably does the same thing as on my airbrush compressor: helps condense out the water and lets it trickle down to a trap or separator at the lowest point.

Lincoln Penn · **Joined:** Wed Feb 02, 2011 9:40 pm **Posts:** 841

CCDW wrote:

Lincoln Penn writes "Air temperature of the compressed air is not even mentioned, as it doesn't matter."

Actually if you read the installation instructions that cover air pumps you will find that a specific length of pipe is required between the pump and the reservoir and a second specific length between the first and second reservoir, if used, for cooling. 26 feet is the recommended length for a 9-1/2" pump and 30' for a compound. I have seen an air pump that ran low on oil on the air side and it got hot enough to blister the paint on the air side of the pump. You compress air, it gets hot.

Once aagin, where is the temperature of the compressed air mentioned?

CCDW · **Joined:** Wed Jan 28, 2009 4:30 pm **Posts:** 211

Referring to The Air Brake, Its Construction and Working, by Marshall M. Kirkman, 1908, Page 92, second paragraph, “These lengths give the greatest cooling capacity without freezing.” And as we all know or should know PV=nRT, as the pressure goes up so does the temperature in a linear fashion, all else being constant.

CCDW · **Joined:** Wed Jan 28, 2009 4:30 pm **Posts:** 211

If we were to visit Air Brake catechism by Robert H Blackhall, 1900, Twelfth edition, we find on page 132 the table of Heat Due to Compression. I am referencing the early air brake texts because with the advent of air pumps the issue of heat due to compression of gases was a very real problem. It is still an issue today with the intercooled combustion air of heavily supercharged internal combustion engines being a common example. From an empirical perspective we can ask why are there so many returns in piping between the air pump and the reservoir. I can assure you it isn’t because there was a surfeit of pipe and a bunch of pipe fitters with a lot of time on their hands who the railroads wanted to keep employed. The pipe radiates heat thereby addressing the issue of moisture and air density to the improvement of operation of the air brake system in general.