Hi,
A couple weeks ago I took the shell off my Atlas SW-9 Switcher just to see what was inside. I even took pictures to make sure I re-assembled it properly!
I disconnected the motor from the U-joints driving the trucks, and it was a bear getting them slipped on again!
I had to have my wife start the motor mount and the body screws because my hands now shake so bad that I can't "hit the hole" to start the screws. After she started the screws, I torqued 'em down.
(During this process, I broke off some of the safety rails on the front & rear platforms.)
When I placed the switcher on the track, it ran backwards, so I had to open up the loco again and reverse the motor, again fighting the U-joints.
After re-assembling the SW-9 (and breaking off the last of the railings), I put it on the track, and it ran in the proper direction, but this time there was no sound!
Back to the hobby room bench, to open up the loco for the 3rd time. I pulled the plug connecting the speaker to the circuit board, and measured the speaker with my ohmmeter. It read open-circuit, like the voice coil was burned out.
Now I'll have to remove the motor for the 3rd time to make room for replacing the speaker!
I should have left everything the way it was in the beginning after those Chinese fellers had put it all together!
bad order....