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  • EMD SD70 series official thread (EXCEPT for ACe version)

  • 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

 #534035  by pablo
 
Tom, I don't think it's about courage.

If you're asking for drawings (as you have before) to color or paint, that's one thing. Are you looking for schematics? Those might not be out since they might include sensitive information.

Dave Becker
 #534242  by GOLDEN-ARM
 
dash7 wrote:Hi, i dont know if this has been covered before but i was wondering if anyone knows what the large opening behind the electrical cabinet, behind the firemans side of the cab was?is it an ac driven t/m blower?and are they fitted with an air start system?,also trying not to push my luck!i was wondering where one could get a mechanical drawing of these engines?,cheers, dash7 :-D
Mods note: thread moved, and combined, into "THE" SD-70 thread
 #535648  by GOLDEN-ARM
 
Author Message
dash7



Joined: 20 May 2007
Posts: 80
Location: sydney, australia
Posted: Thu May 15, 2008 12:37 am Post subject: sd70m-2 t/m blower

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Hi, i dont know if this has been covered before but i was wondering if anyone knows what the large opening behind the electrical cabinet, behind the firemans side of the cab was?is it an ac driven t/m blower?and are they fitted with an air start system?,also trying not to push my luck!i was wondering where one could get a mechanical drawing of these engines?,cheers, dash7
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long live the dash-7

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Chesapeake



Joined: 30 Oct 2004
Posts: 4
Location: Cuyahoga Falls Oh
Posted: Thu May 15, 2008 5:16 pm Post subject:

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The front traction motor blower is located in the box behind the firemans side of the unit, it draws air from the large opening at the rear of the box. I would figure its a AC blower motor, but Im not sure.

SD70M-2's are indeed airstart.
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Chesapeake
Matt M

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 #537455  by bogieman
 
DutchRailnut wrote:one traction inverter is used for HEP reducing unit to 50% traction power.
Each inverter can handle about 60% of the engine power - each has to have more than 50% capacity because of weight shift and the less clean rail seen by the lead truck causing load shift between inverters when operating at high adhesion levels. HEP capacity is limited to about 800kW by the transformer rating, so more than 50% power is always available from the engine in HEP mode.

Dave
 #537457  by bogieman
 
GOLDEN-ARM wrote:Author Message
dash7



Joined: 20 May 2007
Posts: 80
Location: sydney, australia
Posted: Thu May 15, 2008 12:37 am Post subject: sd70m-2 t/m blower

--------------------------------------------------------------------------------

Hi, i dont know if this has been covered before but i was wondering if anyone knows what the large opening behind the electrical cabinet, behind the firemans side of the cab was?is it an ac driven t/m blower?and are they fitted with an air start system?,also trying not to push my luck!i was wondering where one could get a mechanical drawing of these engines?,cheers, dash7
_________________
long live the dash-7

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Chesapeake



Joined: 30 Oct 2004
Posts: 4
Location: Cuyahoga Falls Oh
Posted: Thu May 15, 2008 5:16 pm Post subject:

--------------------------------------------------------------------------------

The front traction motor blower is located in the box behind the firemans side of the unit, it draws air from the large opening at the rear of the box. I would figure its a AC blower motor, but Im not sure.

SD70M-2's are indeed airstart.
_________________
Chesapeake
Matt M

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The blower in the left side walkway box is the alternator blower. It draws unfiltered air and discharges it into the alternator thru a right angle duct. The diodes are not in the ACe and M-2 alternators, they were moved to the electrical locker behind the cab. The motor is an AC motor driven proportional to engine speed via the companion alternator.

Dave
 #609023  by rrfoose
 
Were there ever any orders for SD70M's that were canceled, or orders that were planned but never placed, for that matter?
(I asked about the M's in particular, but if anyone has info on any of the other 70-series orders, that would be fine also!)
 #610476  by USRailFan
 
This is a claim I've seen only one place, I think it was in an old TRAINS, so I don't know if it is true, but anyway: The claim was, that the 25 SD70Ms built for New York Susquehanna & Western (3) and EMD Leasing (22, later sold to CSX) were originally intended for Southern Pacific.
 #610490  by rrfoose
 
USRailFan wrote:This is a claim I've seen only one place, I think it was in an old TRAINS, so I don't know if it is true, but anyway: The claim was, that the 25 SD70Ms built for New York Susquehanna & Western (3) and EMD Leasing (22, later sold to CSX) were originally intended for Southern Pacific.
I'm guessing these would have been canceled (or more like diverted) due to the UP takeover? Maybe UP didn't want them since they didn't have any of that model yet, sort of like what NS/CSX did to CR and their second order for 80MACs. The SP order probably then went to GE for more Dash-9s.
 #612396  by westr
 
USRailFan wrote:Uhm, no. SP's C44-9Ws and AC4400CWs were purchased _before_ the SD70Ms.
I don't know which were ordered first, but accoridng to http://www.utahrails.net/:
SP's SD70Ms were built June-August 1994.
Their C44-9Ws were built May-December 1994.
Their AC4400CWs were built April-October 1995.

It would seem that the SD70Ms and C44-9Ws were ordered about the same time. The AC4400CWs were ordered about a year later. SP also got a large fleet of "SD40M-2s" (rebuilt from SD40s, SD45s & SDP45s) from MK at the same time. According to http://www.trainweb.org/emdloco/946531.htm the EMD Leasing and Susquehanna SD70Ms were built in one order, which suggests that they were someone else's canceled order, and they were built at about the same time as the SP AC4400CWs. I don't know that UP would have had much to do with it as the UP-SP merger didn't occur until September 1996.
 #814789  by jgallaway81
 
Well as other suggested, once I got throttle time, my opinion definitely changed. They ARE crap.

If only I could mate the guts of an SD-40-2 with the cab and carbody styling of the SD-70M-T1, we'd have the perfect engine. (Actually, I'd like to also add-in the sound insulation and vibration dampening of the GE Evolution, and THEN we'd have the PERFECT engine... eh, on third though, also add in the radial trucks from the 80MACs, and the engine would be perfect.... until I think of something else.
 #1005592  by ATSF90East
 
Unfortunately, it appears to be a Photoshop retouch of a NS SD70M-2. Some of the details, like the gaskets and seams for the isolated cab, look like they were added later (The NS locomotives did not have isolated cabs.)

The numbers on the side of the cab and number boards look a little bit off level as compared to the surrounding details, and the SD70M-2 on the long hood matches the color separation line above it, but does not look quite parallel to the walkway below it. The white in the lettering looks much whiter than the white backgrounds on the various warning and safety labels shown on the sides of the locomotive.

That said, it is still a very nice job, and looks very plausible at first glance.

Bruce In KC
 #1005598  by MEC407
 
If you download the SD70M-2 PDF brochure you can see the photo much larger. It does look like a Photoshop job to me, albeit a pretty decent one.
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