Is the engine dark green and orange, or is it dark gray / white / sky blue?? If it’s the latter (GN’s “Big Sky Blue”) paint scheme, it’s almost certainly an old Tyco. I had one of those c. 1972, until recent years I don’t think anyone else made a RTR F unit in GN BSB.
Finally got the time to look at the engine closely. It is an Athearn…has the 4 plastic plugs on the bottom.
I took the shell off and tried to turn the motor by hand but it wouldn’t go. I pushed the motor out and it rotates when I turn it by hand. However, the wheels still won’t turn.
I tried turning the “slotted coupling” (that’s what the part is called according to the assembly diagram I downloaded) but it won’t turn at all on either set of wheels.
I took the gear box clip off the bottom of one set of wheels and see oil residue but can’t see any foreign matter by the gears.
I can’t figure out how to get the “worm housing” off to see if there is a problem inside that. Can someone help me by giving step by step instructions?
Thanks!
The worm housing just pops off. See where the screwdriver is pointing? put the end of the screwdriver under the edge of the cover and pry up on it using the loco frame as a fulcrum while holding the thumb of your other hand lightly on the cover. They like to fly. Carefully remove the worm gear. You don’t want to lose the square bearing on the end of the shaft.
You already have the bottom clip off so I’ll skip that. There’s another clip on top. The screwdriver in the next photo is pointing to it. You remove it the same way as the bottom clip. After the clip is off you should be able to easily pry the truck halves apart.
The third photo shows what you’ll find inside the truck.
Here’s a good tutorial on how to give the locomotive a thorough tune-up…
http://www.mcor-nmra.org/Publications/Articles/Athearn_TuneUp.html
And it does cover the trucks too, so you should be able to trace down the problem.
Good luck!
Go to this site and try to find a document with a loco like the one in question.
http://www.hoseeker.net/athearnmicellaneous.html
Rich
I’d like to thank everyone for helping me with my grandson’s locomotive. I took it all apart, using your wonderful directions, and found all kinds of green gunk on the worm gear. I cleaned all the parts and greased them and put the engine back together. It runs like it was brand new! Again, thank you! I appreciate your help more than you can know.