EMD and GE diesels, how to tell them apart

Notice to all visitors and members of the Train-Sim.Com message forums:
If you plan on using a signature banner in your posts, we would like to remind you that there is a maximum size for banners. That maximum is 450 pixels wide by 120 pixels high, and not to exceed 25k. Your compliance is appreciated. FORUM RULES Problems? There are two common reasons for problems with logging in and posting messages. The first is that you are running a firewall that prevents your messages from being sent to the server. The other is that you have cookies disabled; the DCForum software requires cookies to work properly.

Previous Topic | Next Topic

Printer-friendly copy Email this topic to a friend

Reading Topic #4989

TexasWestern70MacCharter Member · 1174 postsMay 4, 2003 1:03 AM

LAST EDITED ON Aug-21-03 AT 02:54 PM (EDT) by Macster (moderator)

Whether you are new to railroading are an experienced railfan who has trouble identifying the differences between the two major diesel manufacturer diesel types used today, EMD and GE; Here is a BRIEF synopsis of the major differences between locomotives seen on today's modern railroads. I will be pointing out the differences between GE and EMD engines.GE (General Electric)Below the first photo is a General Electric Dash-9W. A 4400 horsepower DC electrical current powered traction motors. Commonly called by rail fans as "Dash 9's" or "c449w's" this is a very typical General Electric "Road Unit" or engine that is normally used on long hauls such as transcontinental runs. The "W" stands for wide cab, or a cab that that's front takes up the entire width of the engine's frame, and has a more spacious interior than engines with "standard" cabs such as this dash-8 b40. EMD and GE diesels, how to tell them apart – image 1
GE engines like this C44-9W with designation of "C" means it has C-C axles arrangements, or 6 wheels (3 axles) per truck (bogie) engines like in the photo above which have four axles (two per truck) have a "B" designation. The number usually like 44 or 40 indicates the amount of horsepower in thousands like 44 is 4400 horsepowerCommon things that can identify typical a GE road locomotive: the radiator "wings" on the back of the locomotive. Distinctly GE. Always have grille louvers under them to vent dynamic brake heat. On the right side the fuel tank has the air reservoirs in an area notched into the tank. GE fuel tanks are also angular. GE wide cab locomotives have a double compound angle slope of the nose as seen on this dash 9. The slope of the angle is normally steep and the only level area of the nose is where the headlight is housed and where is matches up with the windshield. All GE wide cab windshields have two rectangular windows slightly (like .5 degrees) inward. Each window sports two windshield wipers that when off normally point towards the center of the locomotive. EMD and GE diesels, how to tell them apart – image 2
The left side of GE locomotives (any kind) always has a large extension of the same width of the cab that is higher than the walkways. This raised area (indicated by the higher handrail position) stores AC electrical equipment for the locomotive. There are no air reservoirs on the left side of GE fuel tanks and there tank sports a more "smooth" profile, but the angled ness of the fuel tanks persists on both sides of the fuel tank. GE exhaust stacks are also clearly visible on all model types. They are nearly always behind the horn and are silver with scorch marks and soot stains and discoloration by the intense heat from the exhaust. Horns are always put in front of the exhaust stacks and normally have two horns pointing forward and one pointing backwards. Also on the left side mounted on the fuel tank is the warning bell that sounds when the horn is sounded. Also on the left side near the rear of the engine under the radiator wings, is the engine brake wheel. This is connected to a manual linkage and is only use normally when the train looses the normal air brakes.
EMD and GE diesels, how to tell them apart – image 3 EMD (Electro Motive Division)This is a Wide cab EMD diesel the SD70MAC. Unlike the nomenclature for GE engines, which corresponds to the number of wheels and horsepower rating, EMD is a bit odd. SD Stands for "special Duty" as originally designated over 50 years ago. The 70 is the number assigned to this variant of the SD series. The "M" stands for it being a wide cab engine, and "AC" stands for AC electrical current powered to the traction motors. Hence the name "SD70MAC” This particular engine has 4300 horsepower, though nothing in the name indicates that. Horsepower is just something you know by looking in books and magazines about EMD diesels, since it is not easily identifiable by the name.
The left side of the EMD engine sports a distinct EMD characteristic, the blower duct. Not visible on GE engines, EMD made this on their engines clearly visible and ALWAYS on the left side of the engine (with the exception of the SD75M which has one on the right side also) Most modern EMD engines have a "hump" where the blower duct is because the duct if so tall the handrail would hit it otherwise, and there is also a step on the area right above there the duct housing appears to have two recessed square areas, which are actually step supports. The bell on All EMD engines in on the frame instead of the tank, and all EMD fuel tanks are rounded, with air reservoirs on both sides and both sides of the tank look virtually mirror images of each other. EMD engines also have some other major identifiers as being EMD. Unlike the "wings" of GE radiator assemblies, EMD engines have 3 radiator fans, as seen by the 3 raised areas on the roof above the hood mounted radiator grilles. Another major identifier is the radiator grilles, which are on the side, and there always seems to be two sets of them on each side below the radiator fans. Unlike GE diesels the dynamic break fan and grids are not in the same area as the radiator fans. It is hard to see them on an SD70Mac, but grille louvers, which are almost right behind the cab, are the air intake for the dynamic brakes, and the dynamic brake fan on the SD70MAC is right above that on the roof. The cabs for wide cab EMD's are also very identifiable. Normally they have 4 or 6 windshield wipers, and a "teardrop" windshield where the windshield lowers a little bit and matches the contour of the cab nose. Unlike the cab nose of GE's, EMD's are less angular, and have more flat areas on the top. The angle carries all the way back to windows, hence their shape, but also taper out to match the width of the cab. The headlights can be mounted on the nose, as well as the space between the numbers, but this can also be done on GE engines. The horn is behind the exhaust manifold. The manifold on SD70MAC's is flush with the roof line so is not easily seen, but the area right behind the grille above the blower duct, the little bit of area right before the top goes down about 6 inches, is where the exhaust manifold is. EMD and GE diesels, how to tell them apart – image 4 The only major differences between left and right side on an EMD engine is that there is now blower duct, bell, and there is a brake wheel below the radiator grilles.There are also EMD engines, which are older, but of which many are still in use and I will talk about some identifying areas on these engines. EMD also has 4 axle engines with, like this one are designated GP, as this one is a GP60. As you can see EMD also has standard cab engines, also nicknamed "Spartan" cabs. The trucks (bogies) are called "blomberg" trucks and nearly all GP engines had these. EMD and GE diesels, how to tell them apart – image 6 GP stands for general purpose, though this designation was applied over 50 years ago and as SD, their meanings are not related to the work they do today. Both SD and GP engines haul local and long distance freight trains. This engines, a VERY common EMD diesel, the SD40-2, the -2 because it is the second version of the Sd40. This engine is similar to the SD70MAC in where the radiator grilles, and blower duct are located, but is has DC powered traction motors and the dynamic brakes are much more easily visible on older EMD engines than on newer ones. As you can see from the photo of this Santa Fe sd40-2, the "blister" in front of the radiator grilles is where the dynamic brakes are located, they also have two cooling fans instead on one, and the grille louvers are on the blister itself. As seen on the second photo, prior to the early 1980's blower ducts are EMD engines did not take up the whole width of the catwalks on the side of the engine and hence the handrails are not raised to accommodate the blower duct. The rear Santa Fe engine and front BN engine in the second photo are sd40-2's. The fuel tanks are the same as all emd's. The horns on early sd40-2's were mounted on the cab roof, but now they sit between the second dynamic brake fan and first radiator fan. EMD and GE diesels, how to tell them apart – image 7
One minor note, the EMD SD90MAC, and some EMD SD70M have "Flared" radiators. These are exceptions and most EMD engines DO NOT have these distinct features as depicted below, and except fot these "flared" radiators, they are still easily identified as EMD widecabs by the rounded fuel tank and teardrop window design. These can sometimes be confused as GE engines because the radiators looks like GE radiators, but the radiator fans on the top, teardrop cab windows, and rounded fuel tank are another EMD tell-tale giveaway these are EMD engines.SD90MACoddly enough this SD90MAC ( 8209 ) is coupled with a GE engine which shows how it can be confused, but note the fuel tank, windows, and radiator fans above the "flared" radiator than distinguishes it from a GE engine. EMD and GE diesels, how to tell them apart – image 9 "flared" SD70Mas you can see, the "flared" part looks similar to an SD90Mac, but not as dramatic as on an SD90MACI hope you find this information useful when rail fanning so you can tell apart an EMD and GE engine. As far as nomenclature of the different types, that will take time and personal knowledge to get to know the different types. If I identified ALL engines and unique types made by GE and EMD today, this would get very wordy and boring. EMD and GE diesels, how to tell them apart – image 11 Hauling America one pixel at a time
Bill Hemb; train sim repainter http://www.cascadenscale.org/Evergreen/tsdm.htm

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart

RE: EMD and GE diesels, how to tell them apart