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Demoted to B-unit, what does that mean?

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Posted by Anonymous on Wednesday, February 8, 2006 4:29 PM
QUOTE: Originally posted by FundyNorthern

Here's my version of a SOO SD40-2 that is now a B unit. It was originally rebuilt by another railroad, can't recall the name right now. This one is somewhat different than other conversions as the dynamic brakes were moved to where the cab used to be. Mine was made from an Athearn model with parts from several others.


(clck on photo to enlarge)

Bob Boudreau


this unit was originally rebuilt by the burlington Northern
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Posted by Anonymous on Wednesday, February 8, 2006 3:54 PM
QUOTE: Originally posted by 1shado1

QUOTE: Originally posted by electrolove


I also wonder what the difference is between a GP40 and a GP40-2?


"On January 1, 1972, EMD began production of a "Dash 2" line(designations are those of former models with "-2" added) of road locomotives. GMD of Canada built certain existing models into 1972. Dash 2 changes were mainly internal (a modularized electrical control cabinet was a major one). A few spotting features are consistent to the entire line: battery box covers on the frame in front of the cab do not have hinges or latches, but are bolted on; a sight glass to check engine water level appears in the upper half of the hood near the rear of the unit on the right side; and the sloping cab roof extends slightly beyond the rear of the cab."

This is taken directly from "The Second Diesel Spotter's Guide". Tom, you are correct![:D]

Jeff
Also according to the January 1990 issue of Railmodel Journal the final GP-40-2 units have a free flow style blower duct similar to the SD-60.
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Posted by loathar on Tuesday, February 7, 2006 3:29 PM
Wow! Those two locos look creepy with no cabs.(good models, but creepy)
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Posted by waltersrails on Tuesday, February 7, 2006 3:12 PM
tjs couldn't say it better my self

nuet loke the pic of the UP.
I like NS but CSX has the B&O.
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Posted by emdgp92 on Monday, February 6, 2006 9:45 AM
The Pennsylvania (and later PC) had a few GP9B units.

http://www.rr-fallenflags.org/prr/prr3816.jpg
http://www.rr-fallenflags.org/prr/prr3800s.jpg
http://www.rr-fallenflags.org/prr/prr3838ads.jpg
http://www.rr-fallenflags.org/pc/pc3801ags.jpg
http://www.rr-fallenflags.org/pc/pc3839ags.jpg
http://www.rr-fallenflags.org/pc/pc3834bgs.jpg

There was a kit available to convert Athearn's GP9 (really a GP7!) into a B unit, but the manufacturer's name escapes me right now.
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Posted by ProtoWeathering on Sunday, February 5, 2006 8:19 PM
A nice custom made Union Pacific B-unit done by Jim Drennan of Northwestern Illinois Hobbies.

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Posted by mlehman on Sunday, February 5, 2006 9:04 AM
While the cabless conversion was used on some roads as stated above, SSW9389 has it exactly right. In the case of the Rio Grande, they never did rebuild any road-switchers without a cab. They simply stripped the equipment SSW9389 mentioned from the cab to save on maintenance costs on some older units.

On the Rio Grande, the first group of locos converted to B-unit status were the GP-35s. Later on, a few of the GP-30s and GP-40s were similarly converted. Thus these units would not be seen leading a loco lashup, but would rather be placed somewhere in the middle of the consist.
Mike Lehman
Urbana, IL

Mike Lehman

Urbana, IL

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Posted by electrolove on Sunday, February 5, 2006 8:28 AM
Thanks a lot guys for the excellent answers.
Rio Grande Zephyr 5771 from Denver, Colorado to Salt Lake City, Utah "Thru the Rockies"
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Posted by Anonymous on Sunday, February 5, 2006 8:12 AM
Here's my version of a SOO SD40-2 that is now a B unit. It was originally rebuilt by another railroad, can't recall the name right now. This one is somewhat different than other conversions as the dynamic brakes were moved to where the cab used to be. Mine was made from an Athearn model with parts from several others.


(clck on photo to enlarge)

Bob Boudreau
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Posted by CNJ831 on Sunday, February 5, 2006 7:58 AM
As others have alluded to already, a unit that has been demoted to B-unit only status may have "lost" its cab through damage, be unable to meet current saftey and operating standards to meet lead-unit specs, may be less reliable in operation and thus teamed with other units which could "carry" it should it fail out on the road, or in some cases be just too old to be considered for operation other than as a booster unit.

CNJ831
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Posted by SSW9389 on Sunday, February 5, 2006 7:43 AM
In the case of the Rio Grande units being demoted to B unit status, this meant that they could not lead. In the roster book Locomotives of the Rio Grande by the Colorado Railroad Museum it is noted that GP30s #3021-3028, GP35s #3029-3050, and GP40s #3051-3075 were reduced to B unit status in 1972.

From Rio Grande Railroad by Jim Griffin we learn that these B units did not get the newly required chemical toilets nor safety glass required by the Federal Railroad Administration for lead locomotives. Also stripped from the locomotives by Rio Grande were speed recorders, cab sunshades and all seats but the engineer's chair. The engineer's chair was left for hostler moves. [:)]


QUOTE: Originally posted by electrolove

I can read the following on the net about the D&RGW GP40 3066. 'Demoted to B-unit' What does that really mean?

I also wonder what the difference is between a GP40 and a GP40-2?
COTTON BELT: Runs like a Blue Streak!
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Posted by 1shado1 on Sunday, February 5, 2006 2:55 AM
QUOTE: Originally posted by electrolove


I also wonder what the difference is between a GP40 and a GP40-2?


"On January 1, 1972, EMD began production of a "Dash 2" line(designations are those of former models with "-2" added) of road locomotives. GMD of Canada built certain existing models into 1972. Dash 2 changes were mainly internal (a modularized electrical control cabinet was a major one). A few spotting features are consistent to the entire line: battery box covers on the frame in front of the cab do not have hinges or latches, but are bolted on; a sight glass to check engine water level appears in the upper half of the hood near the rear of the unit on the right side; and the sloping cab roof extends slightly beyond the rear of the cab."

This is taken directly from "The Second Diesel Spotter's Guide". Tom, you are correct![:D]

Jeff
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Posted by tjsmrinfo on Sunday, February 5, 2006 2:46 AM
usually when a unit is involved in a major derailment and the cab is messed upretty bad but the prime mover is still running good the shop forces will remove the cab and all cab controls and enclose the cab area. the modern units are pretty much like their ancestors Boosters. these are also called cabless hood units.

the main differences between a gp40 and a gp 40-2 are mainly internal with upgraded electronics. i could be mistaken on that.


hope this helps


tom
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Demoted to B-unit, what does that mean?
Posted by electrolove on Sunday, February 5, 2006 2:38 AM
I can read the following on the net about the D&RGW GP40 3066. 'Demoted to B-unit' What does that really mean?

I also wonder what the difference is between a GP40 and a GP40-2?
Rio Grande Zephyr 5771 from Denver, Colorado to Salt Lake City, Utah "Thru the Rockies"

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