Suggestions before starting
1. Have the right frame of mind, and be patient, don't rush it.
2. Take plenty of pictures before and during the process.
3. Ideally its very convenient to have a magnetic parts tray
to hold the dozen Phillips head screws.
4. Be patient, don't rush it especially removing and installing the cylinders.
5. Good lighting and magnification.
Remove the two screws holding the ash pan, remove the pan to expose the gears.
Gently lift the drive line assembly up out of the gearbox, disconnecting the slip joints.
Drive line assembly.
Remove both trucks (pressure fit) by simply pulling each one up. Next remove the 4 screws shown, 2 are for the cab, the other 2 for a cover plate.
Remove the 2 boiler screws.
Remove the 4 screws (top of picture) that hold the cylinders, then carefully pull the 2 pipes (up) from out of the boiler cradle.
The motor and PCB assembly are remove from the gearbox and placed to the side. The gearbox is in the lower right corner of the picture. (I learned this order of disassembly is easier than what I did when I took these pictures, which explains why the cylinders are already removed)
Remove the cylinders.
One side of the gearbox assembly, simply remove the 2 screws and the plate to service these gears.
I split the opposite side for access to the split gear and shaft assembly I needed to replace. This caused the engine to the cylinders, but the loco would not move the as the power wasn't being transferred to the trucks.
Pictures showing the motor assembly and PCB.
90% of this job is figuring out how to disassemble this intricate loco. Keep your screws and assemblies together so you know what goes with what. I hope this was of some help to you, as there are many of the dead Climax locos out there that are shelf queens, hopefully this will inspire you to repair it. Parts are available at Bachmann Trains.
The shaft assembly below