CSX has reduced the horsepower on their D8-40B's from 4,000 to 2,000. How did they do that?
Gene Perryman
I would think that removing the turbocharger and/or adjusting the fuel rack settings would be involved.
southernalco CSX has reduced the horsepower on their D8-40B's from 4,000 to 2,000. How did they do that? Gene Perryman
They have "micro-CHEC" excitation - which means it's microprocessor controlled, constant HP excitation. (CHEC = Constant Horsepower Excitation Control) To change the HP output by notch - it's a software change.
If they changed the engine speed schedule - which is a good idea in this circumstance, you'd have to adjust the governor also. (making 2000 HP at 1050 RPM from 16 cylinder FDL is "fuelish".)
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
The photo of the loco shows the turbo stack still in place. The photo does not show the whole top.
By "fuelish", I take it that you mean fuel savings ?? Also,by changing the excitation will it load up faster like an EMD?
CSSHEGEWISCH I would think that removing the turbocharger and/or adjusting the fuel rack settings would be involved.
I am not an expert on FDL engines but I am fairly certain that they cannot be operated without the turbo (i.e with a Roots supercharger like earlier EMD's)..
"I Often Dream of Trains"-From the Album of the Same Name by Robyn Hitchcock
On a 2 stroke engine you need a external blower for scavenging while on a 4 stroke they cleverly use the piston to perform this function. A low power ratings the turbo just plugs things up until their is enough heat in the exhaust to spin it up. On the FDL it might speed things up to pick up the load making it more suitable for switching operations. The other thing would be to smaller turbo (i.e. lighter) to speed things up also.
southernalco The photo of the loco shows the turbo stack still in place. The photo does not show the whole top. By "fuelish", I take it that you mean fuel savings ?? Also,by changing the excitation will it load up faster like an EMD?
Most of the time someone gets a wild idea to derate locomotives it's because of some perceived maintenance problem. The fast and easy way is just to back down the excitation. Sometimes they get more sophisticated and adjust the engine speeds to match the "new" rated load.
Can't 'just remove the turbo on the GE locomotive engine, as the cam is set up with a certain degree of overlap between exhaust and intake events. This would be for proper scavenging.
As this unit is long off warranty, I would surmise that custom written software for just a few units would not be worth the cost. This stuff doesn't come for free.
On the other hand, as the CSX fleet is under GE contract maintenance, perhaps some 'motivated' GE field guy came up with a 'simple tweak.'
CPM500
GE are offering a six cylinder in-line version of the GEVO engine which would allow older GE locomotives to meet Tier 2 emissions requirements, in much the same way as a GP40 can be converted to a GP22ECO. This engine is rated at 2300 HP.
This sounds more the sort of thing that a big railroad like CSX would get involved with rather than trying to modify an FDL engine to operate at half its designed power.
But that's just my thoughts.
M636C
M636C GE are offering a six cylinder in-line version of the GEVO engine which would allow older GE locomotives to meet Tier 2 emissions requirements, in much the same way as a GP40 can be converted to a GP22ECO. This engine is rated at 2300 HP. This sounds more the sort of thing that a big railroad like CSX would get involved with rather than trying to modify an FDL engine to operate at half its designed power. But that's just my thoughts. M636C
I think they are just trying to squeeze a few more years out of them as yard/local power and they dropped the HP to keep the fuel consumption and engine maint. down. I think their near term future is probably scrap.
Not all of the B40-8's are being reprogrammed and designated B20-8's. Those that are being redesignated are being used in local freight and MofW service. Specific engines have a notation on their data records that they will remain at 4000 HP and thus won't be converted - at least not at present.
Never too old to have a happy childhood!
I was always a EMD mechanic, and you can remove two pistons and lower the horsepower. This was pretty common with the 20 cylinders. Removing 4 cylinders (two on each end) would effectively knock the horsepower down to 3,000. I don't know how they dropped it down to 2,000.
Ironeagle2006 Having Pulled a Few Wrenches on my Own Equipment and on others Diesel Engines before I started Driving stuff Bigger than Locomotives aka Barge Engines that USED FDL's here is what I would have done First Reset the Governor Rack Settings to prevent wasting Fuel second with the FDL being a 4 Stroke Motor you can DC the Turbo Charger from it how would I know I had to do it on a Tow one time when #1 engine Blew the Turbine Section to HELL. We carried a kit to Bypass the turbo and run at lower Power. The Turbo is not needed until the Engine is Producing over 2500HP anyway at least in the engines we had. Remember the GE Turbo is a Free Spool Design there is Nothing Driving it but Exhaust Gases. So removing it is Not going to cause a problem for the Motor. Lastly Turn down the Excation levels for the Alt so it is not overloading the Motor itself. Remember this with a Diesel all you need is the Right amount of FUEL to make the Horsepower it needs as long as the SOB can get it to Ignite in the Cylinders it will try and Burn it. They do not have any Air Restrictions on them except for Valve Size and Timing on Closure so if you can pack it with enough Air and Fuel you could in Theory make a V-16 710 produce 10000 HP do not know how long it would LIVE.
Having Pulled a Few Wrenches on my Own Equipment and on others Diesel Engines before I started Driving stuff Bigger than Locomotives aka Barge Engines that USED FDL's here is what I would have done First Reset the Governor Rack Settings to prevent wasting Fuel second with the FDL being a 4 Stroke Motor you can DC the Turbo Charger from it how would I know I had to do it on a Tow one time when #1 engine Blew the Turbine Section to HELL. We carried a kit to Bypass the turbo and run at lower Power. The Turbo is not needed until the Engine is Producing over 2500HP anyway at least in the engines we had. Remember the GE Turbo is a Free Spool Design there is Nothing Driving it but Exhaust Gases. So removing it is Not going to cause a problem for the Motor. Lastly Turn down the Excation levels for the Alt so it is not overloading the Motor itself.
Remember this with a Diesel all you need is the Right amount of FUEL to make the Horsepower it needs as long as the SOB can get it to Ignite in the Cylinders it will try and Burn it. They do not have any Air Restrictions on them except for Valve Size and Timing on Closure so if you can pack it with enough Air and Fuel you could in Theory make a V-16 710 produce 10000 HP do not know how long it would LIVE.
I do love this technical talk! Locomotives are also greatly limited by tractive effort because of the size of traction motors and the trucks they are mounted to. If you could fit traction motors twice the size of what they are now into the truck you would have a huge increase in tractive effort. Although you would need a much heavier locomotive to keep the wheels from spinning.
Turbo chargers are a wonderful thing. The twin turbo AC 6000's were quite the design, and you are right, you can keep modifying the turbocharger, valves, and cam and really crank out the horsepower. 10,000 HP wouldn't be that hard to reach at all even for a 12 cylinder. Yet they are going to last 2-3 months before you have a spectacular engine explosion.
I know as was always nervous just tweaking the engine after we rebuilt one. Standing next to a 16 cylinder engine going notch 8 with every door open was a little nerve wracking. A thrown rod or a blown turbo might just slice you right in half. I remember hearing a story of a lady who was killed sitting in her car at a railroad crossing. The turbo blew and shot blades right though the body and into that woman. A engineer once told me he was running notch 8 up a hill and the turbo blew and the turbocharger was laying on the walkway.
CSX being the operation they are would just modify the excitation of the main gen. I would be surprised if they even lowered the rated speed of the engine as that would cost money on an engine that will hardly ever get above notch 5 or 6 anyway.
Thomas 9011 I was always a EMD mechanic, and you can remove two pistons and lower the horsepower. This was pretty common with the 20 cylinders. Removing 4 cylinders (two on each end) would effectively knock the horsepower down to 3,000. I don't know how they dropped it down to 2,000.
IIRC,NS did that with some GP9's, they removed four cylinders and used them for switching and transfer service. I think they may have been rated at 1,200 HP. But I also read that the 567 engines so modified suffered from major vibration issues which could not be corrected, so they were rebuilt again to 567-16 configuration.
As far as the SD45s you mention I remember reading that the engines were significantly reworked to include actually cutting the crankcases down to 16 cylinder length and installing shorter crankshafts.
MK Rail had a proprietary process for this and rebuilt a bunch of units for ESPEE.
I would guess that CSX has changed the fuel rack settings and modified the electronic system to limit RPMs on the derated Dash 8's..
carnej1IIRC,NS did that with some GP9's, they removed four cylinders and used them for switching and transfer service. I think they may have been rated at 1,200 HP. But I also read that the 567 engines so modified suffered from major vibration issues which could not be corrected, so they were rebuilt again to 567-16 configuration.
Geez. No, kidding! They are lucky they didn't break a crankshaft!
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