Athearn SD40-2

[DTomajko]

After removing the shell,make sure the motor is seated in the rubber mounts correctly,(it could be rubbing against the shell).Make sure all the wheelsets are in gauge,(with a NMRA gauge),and that all of the bronze bearings are riding in the metal guides properly.Sometimes the ends of the guides need to be bent slightly at the bottom to hold the bearings properly.Experiment a little,it doesn't take much. Also,run the engine upside down and see if one or more axles binds or jumps excessively.A little grease or oil,(very little),and operating the engine in service can wear in the gears.With a little time and effort,your Athearn engines can be the pride of your fleet.Athearn engines are one of this hobbies most reliable and affordable products ever and as a starting point for super-detailing are hard to beat.Enjoy the hobby and yourself. D.T.,Pa.

[Anonymous]

Try popping off the shell, and running it. Look closely to see if any of the shafts, or flywheels are binding or rubbing on anything. If you don't see anything obvious and it still makes noise, there might be a problem with the gears inside the truck assembly. Nice thing about Athearn engines is you don't need much more than a small screwdriver to get things apart.
Good luck, Todd C.

[Anonymous]

When I was running my CR SD40-2, which is an athearn, I heard a grinding noise but it only did it running foreward. I was wondering if anyone knew what was wrong with it.

Thanks Aaron