Locomotive & Yard Switcher Repair
A switcher can start, idle and sound perfectly normal, and still fail when you notch it up and ask it to move a cut of cars.
It Can Run Fine and Still Not Move Cars
Maybe it will not load.
Maybe it loses power under load. The air system will not behave. A contactor will not pull in. A traction fault appears. Or an older electrical problem has become increasingly difficult to chase.
You already know the locomotive is not doing its job.
Mondak's job is to figure out why.
Yard Switchers & Industrial Locomotives
Mondak works on the locomotives commonly used to move railcars around:
- Rail yards
- Grain facilities
- Refineries
- Industrial plants
- Transload facilities
- Energy facilities
- Maintenance yards
- Private industrial rail operations
Common switcher and industrial locomotive platforms include:
EMD / Electro-Motive
- SW1
- SW7
- SW8
- SW9
- SW1000
- SW1200
- SW1500
- MP15
- MP15DC
- MP15AC
- GP7
- GP9
- GP10 rebuilds
- GP15
- GP38
- GP38-2
GE
- 44-Ton switchers
- 70-Ton switchers
- Older GE industrial locomotives
- Rebuilt GE equipment used in industrial service
ALCO
- S1
- S2
- S3
- S4
- T6
- RS-series locomotives used in switching service
NRE / Genset Locomotives
- 2GS-series
- 3GS-series
- 3GS21B
- Other NRE genset and repowered switchers
And other older, rebuilt or repowered industrial locomotives.
EMD Switchers Are Still Out There Working
A lot of industrial locomotive work still revolves around older EMD equipment.
The SW, MP and GP families have been around a long time, and many are still useful machines.
That includes locomotives powered by EMD 567 and 645-series engines, along with machines that have been repowered or modified over the years.
Mondak can work through problems involving:
- Diesel engine operation
- Fuel systems
- Cooling
- Starting systems
- Governor and engine controls
- Electrical controls
- Generator / alternator-related diagnostics
- Excitation and load-control problems
- Contactors and relays
- Wiring
- Air systems
- Braking systems
- Traction-related faults
The engine making horsepower does not mean that horsepower is reaching the rail.
Diesel-Electric Means Both Sides Have to Work
A switcher is more than a diesel engine on railroad wheels.
The engine drives the electrical power-producing equipment, and the locomotive controls have to properly manage that power before the traction system can use it.
When a locomotive will not load or pull correctly, the problem may involve:
- Engine output
- Generator or alternator excitation
- Load control
- Electrical contactors
- Relays
- Wiring
- Control circuits
- Wheel slip or adhesion controls
- Traction-motor circuits
- Air or brake interlocks
- Operator controls
That is why an engine that sounds healthy can still be attached to a locomotive that will not move cars.
Air & Brake Systems
Industrial locomotives rely heavily on compressed air.
We troubleshoot problems involving:
- Air compressors
- Air leaks
- Reservoir systems
- Valves
- Brake piping
- Brake controls
- Parking brakes
- Air-actuated equipment
- Pressure switches
- Electrical interfaces with the brake system
A locomotive that will not release or build air correctly can be every bit as down as one with an engine failure.
Electrical Troubleshooting on Older Locomotives
Older locomotive electrical systems are their own kind of troubleshooting.
You may be dealing with:
- Large DC control circuits
- Contactors
- Relays
- Resistance grids
- Generator field circuits
- Excitation controls
- Old wiring
- Modified wiring
- Replacement control equipment
- Decades of previous repairs
A schematic helps.
So does understanding that the machine standing in front of us may not be wired exactly the way it left the factory.
We test what is actually there.
NRE Genset & Repowered Switchers
Newer industrial switchers can look very different from a traditional single-engine EMD.
NRE genset locomotives may use multiple smaller industrial diesel engines that start and stop according to power demand.
That can bring together:
- Multiple Cummins engines
- Electronic engine controls
- Generators
- Locomotive controls
- CAN/J1939 communication
- Cooling systems
- Starting and charging systems
- Traction controls
A genset that has lost power may have one failed engine, or a control problem that is keeping an otherwise usable power module offline.
Mondak's Cummins, electronic diagnostics and heavy-equipment experience fit naturally into this type of equipment.
Repowered Locomotives Can Be a Mix of Generations
Older locomotives are often no longer original.
A machine may have:
- A different engine
- Newer electronic controls
- Updated air equipment
- Replacement charging systems
- New wiring
- Modern controllers
- Modified cooling
- Components from several manufacturers
That means the model number on the cab only tells us part of the story.
We start with what is actually in the locomotive today.
Obsolete Parts Are Often Half the Repair
On an older EMD, GE or ALCO switcher, finding the failed component may be the easy part.
Then comes the harder question:
Can you still get one?
Older locomotive components may be:
- Obsolete
- No longer manufactured
- Extremely difficult to source
- Available only rebuilt or used
- Superseded without a direct replacement
- Modified beyond the original configuration
Mondak can look at practical options such as:
- Repairing existing components
- Cross-referencing replacements
- Repairing wiring and controls
- Adapting newer components
- Machining replacement parts
- Making pins, bushings or shafts
- Fabricating mounts or brackets
- Updating electrical or control components where appropriate
On an older switcher, knowing what failed is sometimes only half the job. The other half is figuring out how to keep the locomotive working when the original part no longer exists.
Field Service Where the Locomotive Sits
Most industrial locomotives are not coming to Mondak on a rollback.
We go to them.
Mondak provides field diagnostics and repair for locomotive mechanical, diesel, electrical and related systems.
When a component needs more extensive repair, machining or specialty work, the component can come back to the shop.
The locomotive can stay on the track.
Keep the Yard Moving
Whether you have an EMD SW1500, MP15, GP9, GP38-2, GE industrial switcher, ALCO S-series or NRE genset, you do not need to diagnose the failure before calling.
If you know when it happens, cold, hot, during loading, in a particular throttle position or only while moving cars, that information helps.
Give us the locomotive manufacturer, model, serial or road number, location and what it is doing. We'll start there.