Not exactly sure where to put this one, but move it ever-where you think it should go. I've got probably a 10-15 year old Blue Box Athearn GP40-2 that a family member gave to me for Christmas one year, it ran great for a while, but then something in the front drive truck broke and now its like that truck isn't even attached to the rest of the locomotive drivetrain. I'm fairly certain there is supposed to be something there, but I can't tell and I don't really want to tear the rear assembly apart to find what's missing since I really don't know what to look for (haven't had to take any of my few locomotives apart before). So I guess what I'm asking is does anyone have a schematic breakdown and parts list for that locomotive, or similar. I've tried looking on Athearn's website and I've also shot them an email, so far, no response, so I figured that I'd just give here a shot. I know that I could get a whole new power mechanism which would come complete and just do a body transfer, but this locomotive hasn't given me any other trouble than this, so....I'd rather just repair it if possible. Any/all help will be greatly appreciated.
Yes it is easy to repair these drives. Here is a pic of what it should look like under your GP40-2
http://www.mcor-nmra.org/Publications/Athearn_Tune_Up_Files/AthearnTuneUp002.jpg
I'll bet if you describe what is missing someone could come up with a part # you need to order
I found the schematic for the locomotive,
http://www.hoseeker.org/assemblyexplosionAthearn/Assembly%20Explosion%20Athearn%20GP38-2%20GP40-2%20GP50%201988.jpg
If you could pop the shell off and take a photo that could help us figure out what the problem is.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
if the truck is not attached as you indicate you will need to remove the shell. Older Athearns used one of two different mounting methods. One has small "lugs on the side of the frame near the fuel tank that locate into holes in the side of the shell near the walkway. These are easily seen on the model if it has them. simply pry the shell away from the frame at this point ant it should lift right off. The other method has locking tabs that go down into the fuel tank and can be seen from the bottom. normally the fuel tank bottom will have 4 round holes for the motor mount. if it has the locking tabs there will be 4 squarish holes as well. a small screwdriver can assist you in unlicking these tabs to again, lift the shell off. Once you do this examine both trucks. The trucks have a hole in the ground tab that fits over a pin on the frame. Then the truck is secured with a round top clip that has a couple of pegs sticking out of one end. This clip holds the worm gear assembly in place and secures the truck to the frame. Be sure you have the gear assembly in place properly before you try to snap the clip back down. It may sound complicated as I wrote this but, once you open it up you will see it is fairly straightforward. Plus, you will have one side intact to see how it works.
Dan
thanks everyone for the help, I really appreciate it from the bottom of my heart, especially the schematic of the locomotive. It looks like (at least going from the schematic) that I'm missing the entire worm assembly on the front truck (how it fell out, or came apart, I'll never know, but it did) and that's what I'll need. I'm also going to print this schematic out that way anything else I might need I'll already have a part number for. Again, thank all of y'all for the help on this one, that really gives me what I need to be able to order my parts instead of ordering a whole power mechanism