• Need Some Help with GP Identification

  • 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

  by diburning
 
Hi, I am attempting to model Guilford Rail System (Pan Am) in HO scale and I was wondering what the EXTERNAL differences were between these locos on the prototype:

GP7 - please explain the differences between each phase and what makes it different from the GP9
GP9 - please explain the differences between each phase

GP88 vs GP38-2, what's the external difference?

GP40 vs GP40-2, what's the external difference?

Thank You
  by Allen Hazen
 
For GP-9/GP/7, the standard spotting mark is the number of doors with vents in the battery boxes (below the cab): GP-9 has only one set of louvers, GP-7 has more than one. (I can't help suspecting that, somewhere out there, there might be heavily re-built units of one of these types that look, even in this regard, like the other!)

GP-38-2 should differ from GP-38 in about the same way that GP-40-2 differs from GP-40. An actual carbody sheetmetal difference is that the cab roof has a slight overhang behind the cab in the Dash-2 models, but does not extend beyond the rear cab wall in plain 40-series. Dash-2 units also had a small sight glass in the side of the long hood on the right side (closer to the radiators than to the cab, a bit more than half-way from the walkway to the roof). Some Dash-2 were delivered with "modified" Blomberg trucks (shock absorber over one axle, sometimes a plank with elastomeric cushion instead of the semi-elliptical springs), but since many used trucks from trade-in units this is not a reliable spotting feature of the Dash-2. And battery box covers might show differences under examination.... (For Guilford... I'm not sure any of the Guilford railroads had any pre-Dash-2 40-series units, though maybe MEC had GP-38. Second-hand locomotives don't always look exactly the same as they did when new.)
  by trainiax
 
This is something that I've looked into in great detail. A while back I created phase designations based on those that already existed--or, when phase info was absent or incomplete, based on the detail differences I've observed:

*** GP7 Phases

Phase 1 (1949.10 - 1950.11)
-86" engine room doors
-No box on walkway behind left side cab
-Solid fuel tank skirt
-Sloped pilot plates
-Full-height hood straps before/after engine compartment

Phase 2 (1950.06 - 1953.03)
-Dynamic brakes optional
-Box on walkway behind left side cab
-Slotted fuel tank skirt on units with 1200+ gallon fuel tank (after 1952.03)
-No sloped pilot plates (after 1952.07)
-36" dynamic brake fan (early units), 48" dynamic brake fan (after 1952.08)

Phase 3 (1953.03 - 1953.12)
-82" engine room doors
-Hood straps either stop at top of engine room doors (dynamic brakes) or are absent (no dynamic brakes)

Phase 4 (1954.04)
-GP9 Phase 1a carbody, GP7 internals

*** From Phase 3 GP7 to Phase 1a GP9
-2 louver groups under cab removed
-2 louver groups added to each of first two engine room doors
-2 louver groups removed from 4th door from long hood end
-lower louver group removed from door closest to long hood end

*** GP9 Phases

Phase 1a
-Fabricated pipe handrail stanchions
-Deep fuel tank skirt
-Four 36" radiator fans

Phase 1b
-Stamped channel handrail stanchions

Phase 2
-Lower louver groups removed from generator room doors (behind cab)
-2 louver groups added on 3rd engine room door

Phase 3a
-Fuel filler moved forward
-Shallow fuel tank skirt

Phase 3b
-Louver group under walkway in front of cab replaced by 2 small louver sets

Phase 3c
-Two 48" radiator fans

Phase differences and spotting features of the GP38 and GP40 series are pretty much the same, so I've grouped them:

*** GP38, GP40 phases

Phase 1a - 1965.11 - 1966.04
-Battery box cover under cab: Flat
-Short hood grabirons: Top-mounted, straight
-End plate: Version 1 (Small tabs at bottom steps)
-Fans: Flat center cap
-ECAFB: No
-Radiator intake subscreen: Diamond mesh
-Blower duct: Flat
-Dynamic brake housing taper: Short, angled
-Handrail stanchions: Uneven spacing (closer at rear), bottoms not lined up

Phase 1b - 1966.04 - 1967.09
-Battery box cover under cab: Ribbed

Phase 2a1 - 1967.07 - 1967.10
-End plate: Version 2 (Angled sides at bottom steps)
-Fans: Open-top

Phase 2a2 - 1967.09 - 1968.02
-ECAFB: Yes

Phase 2a3 - 1968.02 - 1968.06
-Short hood grabirons: Bottom-mount, drop

Phase 2b - 1968.06 - 1971.04
-Radiator intake subscreen: Square wire grid

Phase 2c - 1971.04 - 1971.12
-Blower duct: Ribbed
-Dynamic brake housing taper: Long, less tapered
-Handrail stanchions: Even 48" spacing, bottoms lined up

Phase 3 - 1971.12
-End plate: Version 3 (Straight edges, no extension at bottom steps)

*** From late GP38 and GP40 to early GP38-2 and GP40-2

-Bolted (rather than hinged) front battery boxes
-Oblong water-level sight glass (right rear of hood)
-Optional M-type Blomberg trucks
-Modified central air intake and blower duct
-Modified rear hood doors (2-2-2-1 grouping instead of 1-2-4 grouping)
-Lengthened walkway blower duct
-Addition of bolted, rectangular panel around cab side windows
-Stanchions reverted to uneven spacing (closer at rear) similar to early GP38 and GP40
-Larger ECAFB (Electrical cabinet air filter box, on left behind cab)
-Rear cab overhang

*** GP40-2 phases

Phase 1 - 1972.04 - 1975.05
-Battery box in front of cab: Bolted, small louvers
-Battery box under cab: Hinged
-ECAFB: Separated from cab
-Steps: Version 1
-Radiator intakes: Square wire grid
-Short hood: 81" length
-Cab side panel: Bolted, 11 bolts along top/bottom
-Pilot/ends: Straight upper end plate corners, no raised coupler cut lever, no front anticlimber
-Rear upper pilot/drop step area: Version 1, inward-facing handrail stanchion supports
-Radiator fans: Flat top
-Exhaust: Raised stack
-Blower duct: Flat, wide, two ribs, no raised walkway
-Frame side sill: Narrow over air reservoirs, wide at ends

Phase 2a - 1976.01 - 1978.12
-Battery box in front of cab: Bolted, large louvers
-Battery box under cab: Lift-off tabs
-ECAFB: Flush with cab
-Steps: Version 2
-Radiator intakes: Corrugated
-Short hood: 88" length, vent on right side
-Cab side panel: Bolted, 13 bolts along top/bottom
-Pilot/ends: Notched upper end plate corners, raised coupler cut lever, front anticlimber (2 versions, depending on railroad)
-Rear upper pilot/drop step area: Version 2, outward-facing handrail stanchion supports

Phase 2b - 1979.01 - 1979.11
-Cab side panel: Welded

Phase 2c - 1979.12 - 1981.03
-Battery box in front of cab: Horizontal rib added (some railroads)
-Radiator fans: Q-type
-Exhaust: Raised silencer, opening at rear

Phase 2d - 1981.05 - 1982.07
-Short hood: Bolted hatch added on top

Phase 3 - 1983.03 - 1986.12
-Battery box in front of cab: Latched, lift-off tabs
-Blower duct: Angled, narrow, no ribs, raised walkway ("laundry chute")
-Exhaust: Raised silencer, opening at front
-Frame side sill: Narrow over entire length

Phases on the GP38-2 are similar to the GP40-2, except that the GP38-2 has an additional phase at the beginning. Very early GP38-2's retained the long radiator intake and wider-spaced fans of the GP38, while later units (accounting for most of production) had closer-spaced fans and shorter radiator intakes.

Some of the differences between the "non Dash-2" and "Dash-2" units are pretty well-known, but there are many more obscure differences that are less well-known. If you compare, say, an early GP40 with a late-production GP40-2, there is hardly a single piece of sheetmetal that is shared between them and they almost look like two completely different models.
  by NV290
 
trainiax wrote:*** GP40-2 phases

Phase 1 - 1972.04 - 1975.05
-Battery box in front of cab: Bolted, small louvers
-Battery box under cab: Hinged

Phase 2a - 1976.01 - 1978.12
-Battery box in front of cab: Bolted, large louvers
-Battery box under cab: Lift-off tabs
-ECAFB: Flush with cab
-Steps: Version 2
-Radiator intakes: Corrugated
-Short hood: 88" length, vent on right side
-Cab side panel: Bolted, 13 bolts along top/bottom
-Pilot/ends: Notched upper end plate corners, raised coupler cut lever, front anticlimber (2 versions, depending on railroad)
-Rear upper pilot/drop step area: Version 2, outward-facing handrail stanchion supports

Phase 2b - 1979.01 - 1979.11
-Cab side panel: Welded

Phase 2c - 1979.12 - 1981.03
-Battery box in front of cab: Horizontal rib added (some railroads)
-Radiator fans: Q-type
-Exhaust: Raised silencer, opening at rear

Phase 2d - 1981.05 - 1982.07
-Short hood: Bolted hatch added on top

Phase 3 - 1983.03 - 1986.12
-Battery box in front of cab: Latched, lift-off tabs
-Blower duct: Angled, narrow, no ribs, raised walkway ("laundry chute")
-Exhaust: Raised silencer, opening at front
-Frame side sill: Narrow over entire length

Phases on the GP38-2 are similar to the GP40-2, except that the GP38-2 has an additional phase at the beginning. Very early GP38-2's retained the long radiator intake and wider-spaced fans of the GP38, while later units (accounting for most of production) had closer-spaced fans and shorter radiator intakes.

Some of the differences between the "non Dash-2" and "Dash-2" units are pretty well-known, but there are many more obscure differences that are less well-known. If you compare, say, an early GP40 with a late-production GP40-2, there is hardly a single piece of sheetmetal that is shared between them and they almost look like two completely different models.
In the items highlighted in red...

EMD GP40's (Or SD's for that matter) have never had batteries mounted under the cab. Under the cab on the right side is the air brake rack. On the left side is simply an access door to the under cab compartment. It's where you usually find the event recorder, Equl reservoir, etc.

And on the red highlighted exhaust stack. Turbocharged EMD's always have the turbo at the rear of the prime mover which will always put the exhust stack at the front of the locomotive, rear of the prime mover.

And for things like battery doors, the type of doors were not always standard. Many railroads opted for louvers, some wanted the large "mailslot" type holes to allow easy battery top washing. Some wanted doors, others wanted bolt on hatches. You cannot accuratley class the age of a loco based on things like access doors. Uncoupling levers, cab vents, nose lengths, nose access hatches and pilots were also items that were specific to a customer. And some railroads, nameley the Canadian roads had even more oddball features that can further confuse things.


The only way to be certain that what you are seeing is in fact a GP40 or a GP40-2 is to #1, see the back cab wall. A DASH 2 model will always have the long horizontal access door mounted halfway up the wall that holds all the control cards.

OR, #2, look on the right side long hood a little more then halfway back. If you see an oval window in one of the access doors, then more then likley it is a DASH 2 model.

As for ID-ing Guilford units, it's simple. Guilford owns ZERO GP38's of any kind. All there GP40's are numbered in the 300 series and they are all standard GP40's, NOT DASH 2 units.
As for GP40-2's, easier still. They are all numbered in the 500 series and all have the "wide body" style Canadian cab. While these are not classed as simple GP40-2's because of the specialized features, they are based on that model and use the same mechanical and electrical systems of the standard GP40-2. The major differences are the CN Designed traction control system, Rear hood mounted batteries, Dofasco trucks, class lights, snow steps, lift rings, single rear headlight, no rear number boards and all the other typical CN items.
  by MEC407
 
NV290 wrote:Guilford owns ZERO GP38's of any kind.
You're forgetting BM 252 (ex-MEC 252) -- a GP38. Still very much in existence and still very much on the PAR roster. :-D
NV290 wrote:OR, #2, look on the right side long hood a little more then halfway back. If you see an oval window in one of the access doors, then more then likley it is a DASH 2 model.
Agreed, although the exception to this rule would be units that have been upgraded/rebuilt to Dash 2 specs. Generally the little window is not included as part of the upgrade/rebuild. An example would be some of the GATX (ex-LLPX) GP38-2s, which were rebuilt from GP38s. Externally they look like a standard GP38, but internally they're GP38-2s. And then there's the issue of railroads and leasing companies taking GP40s and rebuilding them as GP38-2s. Sometimes they remove the #2 radiator fan, sometimes they don't... which leads to locomotives that look like a cross between a GP38 and a GP40. Thoroughly confusing for the average trackside observer!
  by NV290
 
MEC407 wrote:
NV290 wrote:Guilford owns ZERO GP38's of any kind.
You're forgetting BM 252 (ex-MEC 252) -- a GP38. Still very much in existence and still very much on the PAR roster. :-D !

I forgot about those. Good call.
NV290 wrote:OR, #2, look on the right side long hood a little more then halfway back. If you see an oval window in one of the access doors, then more then likley it is a DASH 2 model.
MEC407 wrote:Agreed, although the exception to this rule would be units that have been upgraded/rebuilt to Dash 2 specs. Generally the little window is not included as part of the upgrade/rebuild. An example would be some of the GATX (ex-LLPX) GP38-2s, which were rebuilt from GP38s. Externally they look like a standard GP38, but internally they're GP38-2s. And then there's the issue of railroads and leasing companies taking GP40s and rebuilding them as GP38-2s. Sometimes they remove the #2 radiator fan, sometimes they don't... which leads to locomotives that look like a cross between a GP38 and a GP40. Thoroughly confusing for the average trackside observer!
Agreed as well. I was simply talking about from the factory. In the rebuilding world, anything goes.
  by Allen Hazen
 
Re:
"And on the red highlighted exhaust stack. Turbocharged EMD's always have the turbo at the rear of the prime mover which will always put the exhust stack at the front of the locomotive, rear of the prime mover."
Whereas GE (and Alco) had the turbocharger at the non-generator ("front") end of the engine, so the stack is further back on the locomotive, just forward of the radiators. ... But... In Australia (where hurricanes rotate clockwise and swans are black) things are different. GE locomotives (such as the "NR" class, a lightweight derivative of the Dash-9) the stack is where you'd expect an EMD stack to be, between the cab and the engine room, and recent EMD types have the stack closer to the rear of the locomotive! I think it's because of noise regulations: exhaust in both makes of locomotive is run through a giant muffler over the engine to the far end -- whichever end that is -- of the engine.