Athearn RePower Kits

Athearn, ROCO, etc Diesel Locomotives

Want smooth, powerful operation for your diesels, especially the now-discontinued Athearn “Blue Box” diesel locomotives? NWSL’s repower kits are the answer, and they’re DCC ready if you need it.

These repower kits come with pre-installed flywheels, pre-soldered motor leads, plus U-joints and NWSL’s Qwik Mount mounting material. You remove the factory motor and driveshafts, install the repower kit, test the unit, then secure the motor to the chassis using the “silicone sealant” method described in the instructions (included with kit).

The NWSL repower kit comes in four versions and all use the same motor, the NWSL 2032D-9. The four configurations allow for different types of engines. Standard width and length engines, such as the F7, PA, FP40, etc. have enough length to allow for two flywheels and enough width for an 18mm (0.714") diameter flywheel. Standard width but narrow body units, such as SD40, GP7, GE-8, SD90, etc. have less room to work with, so the motor is fitted with two 16mm (0.630") flywheels and you install the motor on edge to fit. We also have two versions for switchers and other short locomotives; these have only one flywheel due to length restrictions inside the engine. This shorter version is also available in both a narrow and wide flywheel to accommodate for different widths.

Which one do you need? Pop off the shell and measure! Check the width of the shell cavity. If it’s 21mm (0.826") or wider, go with the standard width version. Narrower? Go with the narrow version. Next, check length. If your model already has two flywheels, go with the longer version of the repower kit. Not sure? Measure how much length you have to work with, then refer to the images below. The NWSL repower kits are a bit more compact than the factory power plants they replace; note also that the flywheels are pressed on and can be moved a bit if need be. The motor shafts are supplied full length; if need be these can be trimmed back to provide more room. The NWSL driveshafts are adjustable and can be made to fit whatever configuration you come up with. See tutorials at