[Accrs-ho] Athearn Genesis 3 Axle Trucks

[ACCRS HO Scale]

There is a known problem with Athearn Genesis and Athearn RTR models that use a EMD type 3 axle truck as pictured below.  These newer trucks are an improvement over the original SD40-2 trucks that first came out in the 1980’s.

The major issue with these is electrical conductivity between the wheels and the pick-up wires.  As you can see the design is basically the same as the original.

Not all models will exhibit this problem – is you get one without any problems then you are very lucky.  The “quick test” to see if you have a problem truck is to lift one the front truck off the rails while the rear is still on the rails and see if the model still get power to the motor.  On a sound equipped model this is easy to do since the sound decoder will die if there is a problem.   Repeat on the other truck.

I’ve found this problem on SD45-2, SD60M models.  It appears that the problems still exist even on the newest releases.

Root Cause – the black coating on the side plate acts as an insulator.

Fixing – If you can’t return the model for a replacement with one that is proven to have both trucks working correctly,  you can fix this yourself.  You will have to remove the trucks and disassemble them.  Then scrape or file the black metal coating on the three bearing channel edges on each side plate that contact the bearings.  Coat the exposed metal with a film of light oil.   Next problem point is the rivet that connects the pick-up contact to the side plate.  The rivet needs a clean contact surface to conduct and one way is to scrape the coating away from the side plate and rivet edge and then apply a solder bridge between the two.   Next verified that the contact pick-up is getting conductivity to from the.   If still not working,  the rivet maybe coated on both side.  Feel free to contact me about solving that problem.  Using a multi-meter with conductivity test mode is very helpful.   After you apply solder you can clean off the flux with alcohol, dry and paint a flat black color.   You have to be careful with the solder approach – you’ll need at least a 30-40 watt iron.   Be careful not to over heat and warp the plastic.  Just touch and go.


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