Atlas GP39-2 Not Running


brickbuilder711

brickbuilder711

FEC Train 222
Hi guys,
I have an Atlas GP39-2 (CSX YN3) that I bought in 2011 from Warricks Hobby Store, so the model was tested and functional. Unfortunately, I don't have a working layout, so I didn't run it for the four years since. Unfortunately, I had it dropped from a 3 foot high bedside drawer when moving it and the back truck sort of got loose (cosmetic damage was very minor, actually with only a piece of the pilot bent). Front truck is fine. It only appears that the back truck got detached from the main frame. I took it to a friend's house to have the engine tested since he has a DCC assembly (we tried both DCC and DC) and the unit would not move a muscle. The motor made no noise, only a minor vibration.

This leaves me to diagnosis and asking what is the problem. I have a suspicion that the unit would not work for a different reason. The locomotive put up with Florida humidity for quite some time, I don't remember how long but whenever I displayed it outside, it was months at a time. Did a minor drop that only affected the back of the locomotive kill the whole unit? Or did the humidity play a role? Or maybe not running it for so long?

I can post pics upon request.

Thanks for any help.
 
If it was making a slight vibration, that probably means the motor was getting power but just couldn't turn. Most likely the grease in the truck gears has gone hard, preventing turning. Otherwise maybe when it was dropped a gear has moved and jammed it up.
 
Try disconnecting the driveshafts to both trucks, and see if the motor will run. Then try each truck to make sure the worm will rotate without binding.
 
tootnkumin said:
If it was making a slight vibration, that probably means the motor was getting power but just couldn't turn. Most likely the grease in the truck gears has gone hard, preventing turning. Otherwise maybe when it was dropped a gear has moved and jammed it up.
Click to expand...

This has happened to me on more then one occasion, a little drop of oil on the gears and gentle force to manually move the gears solved the problem. This is why I only use synthetic grease. I don't know what the old stuff was made from. but it can get rock hard and seize up the gears.

Another locomotive I bought new sealed in the box from eBay did the same as yours. I oiled the gears lightly and moved them manually to distribute the oil and it worked like new. Then I used synthetic grease and it has been running great ever since.

Both of those solutions I have used on spur gears, but if it is a worm gear you may have to disconnect the drive shafts as Terry said.

There is a question for you Terry: Can you manually rotate the worm gear by turning the wheels in a locomotive without disconnecting the drive shaft or will it be too much force with out the motor turning?
 
Can you manually rotate the worm gear by turning the wheels in a locomotive without disconnecting the drive shaft or will it be too much force with out the motor turning?

No, the gear ratio is too steep. If you can see the flywheel from under the chassis, you can take something and turn the flywheel to rotate the assembly.

Joe
 
Since the motor is vibrating it sounds like it is getting electricity (do the headlights come on?). I agree with a few of the others theories. One of the drops might have jammed a u-joint or broken a worm gear so the motor cannot turn. Or both drive shafts have broken and the motor isn't vibrating but turning smoothly with no load. OR, the lubrication has petrified.

Best way is to just open it up and figure out what is going on inside.
 
josephbw said:
Can you manually rotate the worm gear by turning the wheels in a locomotive without disconnecting the drive shaft or will it be too much force with out the motor turning?

No, the gear ratio is too steep. If you can see the flywheel from under the chassis, you can take something and turn the flywheel to rotate the assembly.

Joe
Click to expand...

Thank you Joe :)
 
Thanks for the responses guys and sorry that I followed up so late, the semester just started. Yes, power is going to the lights. I will take a closer look on my next free break. I don't think a worm gear could have been busted based on the fall, the shell is almost completely unscathed so I doubt the inside would be impacted. The grease drying up sounds very plausible.
 
You must log in or register to reply here.



Back
Top