I Know the DDA40X's had engines and the like just for this locomotive class. Now, on the 6936, are these original engines stil on her, or have more standard item been placed in her?
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I had always thought that the engines were the same as what was used in a SD40. Just bolt a replacement inplace.
I would guess that the engines are original blocks, but maybe over the years it might have had a overhaul, (new cylinders).
Dan
No, the 645 diesel engines in the DDA40X model locomotives ere 16-546E3A with a max full load rated RPM of 950, and a special "new design" high capacity turbocharger. The SD40 model had a "regular" turbocharged 16-645E3 model engine with a full load rated 900 RPM.
The UP DDA40X #6936 no longer has her "original" engines, by specific serial numbers, is is still equipped with the 950 RPM 16-645E3A high HP rated engines. An additional added "feature", and possibly little known fact about the DDA40X models was, there are the absolutest LOUDEST units EMD ever produced, because they have NO exhaust silencers, so you hear the maximum "music" from those twin 950 PRM, 3300 HP engines when at full load.
Originally Posted by Hot Water:
No, the 645 diesel engines in the DDA40X model locomotives ere 16-546E3A with a max full load rated RPM of 950, and a special "new design" high capacity turbocharger. The SD40 model had a "regular" turbocharged 16-645E3 model engine with a full load rated 900 RPM.
The UP DDA40X #6936 no longer has her "original" engines, by specific serial numbers, is is still equipped with the 950 RPM 16-645E3A high HP rated engines. An additional added "feature", and possibly little known fact about the DDA40X models was, there are the absolutest LOUDEST units EMD ever produced, because they have NO exhaust silencers, so you hear the maximum "music" from those twin 950 PRM, 3300 HP engines when at full load.
Can you say HOT ROD??
What was used in the GP40? The general rumor/urban legend was that the DDA40X was a pair of GP40's under the hood.
Originally Posted by AGHRMatt:
Can you say HOT ROD??
Absolutely!
What was used in the GP40? The general rumor/urban legend was that the DDA40X was a pair of GP40's under the hood.
The GP40, had the same engine that was in the SD40, i.e. the "40 series". The DDA40X was a LOT more than just "two GP40s under the hood".
I was told the F45/FP45 were the loudest single motor engines because the Cowl body acted like a amplifier. A couple of retired Santa Fe engineers have said they were not happy when one of these engines was the lead unit when they were called.
Originally Posted by Chuck Sartor:
I was told the F45/FP45 were the loudest single motor engines because the Cowl body acted like a amplifier.
Yes, inside the cab you are correct, but the actual exhaust noise to the outside person at trackside, was nowhere near as loud as a DDA40X.
A couple of retired Santa Fe engineers have said they were not happy when one of these engines was the lead unit when they were called.
I can fully agree with that.
Originally Posted by Hot Water:
Originally Posted by AGHRMatt:
Can you say HOT ROD??
Absolutely!
What was used in the GP40? The general rumor/urban legend was that the DDA40X was a pair of GP40's under the hood.
The GP40, had the same engine that was in the SD40, i.e. the "40 series". The DDA40X was a LOT more than just "two GP40s under the hood".
Thanks.
Did EMD ever consider using this mill in any other production locomotive...or would they just tell you to go buy an SD45? At 3300HP on a 645 V16, you're getting pretty close, in my book. Glad to hear about the volume factor, somebody had to be the loudest, and it might as well be the BIG Guys !
Originally Posted by jaygee:
Did EMD ever consider using this mill in any other production locomotive.
The "40-2" line came out in 1972, and a 3000 HP for a 4-axle unit, that was pretty much all that could EFFECTIVELY be put to the rail. Upon the development of the "Super Series" wheel adhesion control, then more HP could be applied to the rail, and thus came the "50 Series" of units at 3500/3600 HP.
..or would they just tell you to go buy an SD45?
No, not all railroads were enthused about the 3600 HP 20-645E3 engine. When the "-2" line came out in 1972, the SD45-2 was a better performer, the the SD50 provided the best of both worlds, i.e 16 cylinder engine with 3500/3600 HP, with "Super Series".
At 3300HP on a 645 V16, you're getting pretty close, in my book.
Actually, the 16-645E3A engines in the DDA40X were actually rated at 3600 "corrected" HP, thus providing a full 3300 HP for traction.
Glad to hear about the volume factor, somebody had to be the loudest, and it might as well be the BIG Guys !
I believe that the 645E3A was also used in the 4200 HP, 20 cylinder SD45X units.
Stuart
One moring the 6936 was at the Amtrak Station in Houston with passenger cars for an inspection train. Now I know why the engine sent sparks into the night while idling!
I was a design engineer at EMD working on the manufacture of the UP DDA40x locomotives. These locomotives were being produced with a generation switch from a discrete control system to the first modular design with integrated circuits. It was considered a dash 1 series control system versus the release of the dash 2 series in 1972. The dda40x is the only locomotive with these dash 1 modules. The engine was rated at 3300 traction horsepower and was the predesessor to the 16-645E3B engine. When the SD50 series was introduced it had a 16-645F engine rated at 3500 traction horsepower. This was a terrible engine with many turbo and power assembly problems.
Can the 6936 still run? Have not heard anything about it lately. Or is it the diesel version of 3985, that is,"semi-retired"?
For anyone wishing to experience the 6900s at work, I highly recommend a program titled "Union Pacific 6900s: The Centennials." Originally released in VHS format by Video Rails in 1985, the video features numerous trackside scenes showing trains with impressive multiple unit consists, a cab ride and a walk-around explaining the various features of the locomotives. There is much excellent footage showing these units at work and you can really hear them howling.
http://pentrex.com/vr006dvd.html
Bob
I saw it in Cheyenne in August. Still working.
