I have a N scale 1997 built Atlas GP9TT that has suddenly developed a clacking noise in the trucks. Any one have a solution on how to fix it? I have taken the engine apart and have seen no dirt or grit. There does seem to be something catching in the gears when you rotate them. Lubricating did not help. I’m at a lost with this one. Bob J.
Most likely some fine debris in the truck gears if the gears are open in the truck bottoms and not fully encased. Completely clean all lube out of the trucks and slowly rotate the gear train while looking for any remaining debris. Next idea is you could have damaged or missing gear teeth caused by a piece of hard debris.That would become evident up the examination once cleaned. Also look at the gears in the gear tower that transfer the drive to the trucks for the same.
Thanks for your input very much appreciated. . Not sure what the problem was. I removed the trucks again and figured out how to pop the gears out from their sockets. Checked them over and found nothing. Blew the whole truck assembly with compressed air (on low pressure). Reassembled and put it back on the lay out. All is well once again. (OK, now I'm Happy)
I have the same problem about once a month. The cut outs in the bottom of the truck are a "vacuum" for any ground foam or loose ballast lying between the rails. Not sure why they make the trucks with the cut outs? I thought I read somewhere where someone put tape on the bottom of the trucks.