So, you’ve just acquired a fantastic SD70MAC model train, perhaps from Athearn Genesis known for their detailed locomotives, and you’re eager to get under the hood, maybe to install a decoder or just to admire the inner workings. A common first hurdle is safely removing the shell. Many model railroaders, especially those new to Athearn Genesis models and their robust “Genesis Truck” designs, find themselves a bit hesitant, worried about damaging their prized locomotive. Let’s walk through the process of shell removal and address some common issues you might encounter with your Genesis truck equipped SD70MAC.
Firstly, tackling the shell removal on your SD70MAC, specifically designed with the intricate details associated with Genesis models, can feel daunting. The manufacturer often suggests squeezing the long hood near the Q-fans. For those unfamiliar, these are indeed the three prominent fans on top of the hood, designed for engine cooling in the prototype. However, applying pressure without knowing exactly where to push can be nerve-wracking.
A safer and more precise method involves locating the shell clips from underneath. Grab a flashlight and carefully inspect the underside of the locomotive frame. Looking through the openings above the trucks – both in front of the rear truck and behind the front truck – you’ll spot where the retaining clips peek through the frame. These clips are what securely hold the shell to the chassis, a key feature in the robust construction of Genesis series models and their trucks.
Using a fine, flat-head screwdriver, gently work to release these clips. It’s best to start with one side and then move to the other. Patience is key here. Be mindful of the delicate grab irons at the front of the locomotive and the handrails that attach to the cab. These are usually press-fit and can be gently pulled out of their sockets if they aren’t glued, giving you clearance to lift the shell. Remember to exercise caution and avoid yanking the shell off, as there are wires connecting the lights in the shell to the chassis.
Speaking of what’s underneath, the “genesis truck” design is known for its performance, but like any intricate mechanism, issues can arise. One common problem, not exclusive to Genesis trucks but relevant to all model locomotives, is derailment, particularly on turnouts. If your Athearn six-axle locomotives are experiencing derailments, especially on Atlas turnouts, it might be due to the points being slightly lower than the stock rail. This difference can cause the wheels to ride up and split the switch. Testing your locomotive’s frame alone can help isolate such issues.
Another potential problem, and one that was encountered in the original post, is a clicking noise originating from the trucks. Disassembling the truck down to its gears can help diagnose this. In one instance, a burr on the worm gear was the culprit. A bit of careful filing and using grease instead of light oil can significantly improve the smoothness and quietness of the Genesis truck operation. Proper lubrication is crucial for the longevity and performance of these intricate truck assemblies.
Finally, many modelers upgrade their locomotives with decoders to take advantage of features like ditch lights. The SD70MAC, especially in versions like the NS model mentioned, typically has eight wires running to the shell-mounted lights, including those for the ditch lights. When reinstalling the shell after maintenance or decoder installation, remember to carefully reconnect these wires. The power pickups in these locomotives are neatly designed with their own grooves, which helps keep them out of the way during reassembly.
In conclusion, working with your Athearn Genesis SD70MAC and its “genesis truck” design requires a blend of care and methodical approach. Shell removal is straightforward once you know where the clips are located. Troubleshooting issues like derailments and noises often involves careful inspection and maintenance of the trucks. With these tips, you can confidently maintain and enhance your Genesis series locomotive for years of reliable operation on your model railroad.
