CSX’s Huntington Heavy Repair shop in West Virginia is reworking more than a dozen EMD SD70ACs and the first finished product could return to revenue service in early September. Jonathan Karson, a shift plant superintendent at Huntington, tells Trains News Wire that the program is more of an upgrade for the diesels than a rebuild. The primary drive, Karson says, is the new Mitsubishi MELCO control systems which are replacing the original Siemens control systems in the SD70ACs. Karson says the hope is that the new systems will enhance performance of the SD70AC fleet.
A total of 25 units will see the upgrade. The EMD 710 prime movers are also being rebuilt with a refurbished engine block and all new components, and the locomotive cabs are being redone with new floors and ceilings, LED lighting and new display screens, among other upgrades. Karson says a new CCB2 airbrake system is being installed, and the trucks are also being rebuilt or replaced with new wheel sets being added. Karson says the upgrades will result in newer components being on the locomotives making it easier to service and replace parts. “The system is primarily the same as far as mechanically, as far as working on them, but the parts are easy to get, too,” Karson says.
A new camera system is also being installed in each upgraded locomotive and the first 10 rebuilds will have an electric refrigerator installed in the cab. Once a stripped down SD70AC enters the rebuild process, it takes about six weeks to complete and return it to revenue service, Karson says.
In tests, throttle response in the locomotive has improved. “It’s a lot smoother ride. You’ve got a better transference of power from the engine to the wheel,” Karson says. “A big difference is tractive effort and from what one of our electricians was telling us, he noticed that big difference in the response time with the throttle and you don’t get that jumpiness and hesitation.”
Karson says the CSX SD70AC fleet is, structurally, in good condition, which has helped in moving the project along. He says the current plan is to have the first upgraded SD70AC back in revenue service in the first week of September. He said the plans call for 15 of the locomotives to be upgraded by the end of 2019 and another 10 to be completed in 2020. “These initial 25 will be a data collection bed for the first 12 months or so,” Karson says. “It would be impractical to try to do each and every one right now, and we typically have some sort of test bed with any project we do. We did that with the (SD40-3) program and that’s what we’re doing here. Once the data is collected from that, a determination will be reached whether it will be worth it do to the rest of the fleet.”
The Huntington shops will add a special decal onto each upgraded SD70AC to distinguish the locomotive from those not included in the program. CSX currently rosters approximately 200 SD70ACs in the railroad’s 4500 series and in the number series 4700-4830, being built from 1997 through 2006, according to the website The Diesel Shop. The 25 locomotives in the rebuild program are all in the 4500 series.
It seems as if CSX is starting to take a page out of Northfolk & Southerns rebuild an upgrade book. When u have a good core, rebuild an fix the problems for a lot less than new. I’m sure rebuilding those AC motors are cheaper than what Northfolk an Southern spending on their DC to AC program.
So mechanically and electronically the upgraded SD70MACs will be identical to an SD70ACE…all of which CSX has purged from its roster.
Great news.
Nice to see that CSX is rebuilding some of its SD70MAC’s aka SD70ACs I always loved seeing these CSX SD70MAC’s when they frequently visited Southern California on BNSF and Union Pacific Train’s. Hopefully CSX will also purchase more SD70ACe-T4s as well as apparently CSX likes them.
A big problem with these units is if you have a ground fault or other problem with a single traction motor, you have to cut out the entire truck and loose the power of the remaining two good motors on that truck, hence half the locomotive’s traction output. I would hope that the new systems correct this problem! You need an AC inverter for each traction motor, not the entire truck! This is one reason GEs have been purchased over EMD to such a great extent on CSX.