Mikado Disassembly

General

There are 2 versions, the difference seems to be the later version has an additional switch. More later.

The tender power pickups are usually wired incorrectly. There are 2 sections to the power pc board in the loco, one is for battery and one is for track power. It seems that the pickups for the tender are wired to the battery side of the board. Thus when running track power, the tender pickups are inoperative. When running battery, the battery power is applied to the rails.

Moving the tender pickup wires will solve the problem. A more detailed explanation is coming.

Disassembly:

Motor Block removal:

Remove the main rod (to the piston) and the valve rod (the gear oscillates back and forth). Rotate the wheels until both hex head screws are visible, and then carefully remove. If they are way tight, could be loctited, if you suspect this is true, heat the hex head with a large hot soldering iron. Remember how the valve gear linkage is on, crank part points back towards the axle.

Be sure to put the hex screws and the washers back into the axle ends so you do not lose them!

Unscrew the motor block, 2 large screws just behind the rear drivers, and 2 smaller screws on the very front end of the motor block. There are 3 small screws here, just remove the outer 2. (The center one holds the block itself together)

Lift the block up, and unplug the connector near the motor.

Boiler:

First, remove the 4 small screws from the corners of the cab from underneath. You should be able to remove the cab now, but it might be tight, wiggle it fore and aft. If it doesn not come off, wait until the boiler is loose, and wiggle the cab loose while you are lifting the front end of the boiler. The windows will fall out. 

Release the handrails from the front of the boiler, just the 2 furthest forward stanchions. The handrails just pop up and inwards, you can see the stanchions are open in the back.

Remove the single screw on top of the boiler, just behind the smoke stack.

Put the loco on it's back, and remove the 4 small screws that hold the boiler on, 2 just forward of the firebox, and 2 just behind the cylinders.

Flip the loco back upright CAREFULLY, the boiler will now be loose, so don't lift it by the boiler to do this!

Wiggle the boiler off from the front.

Kadee couplers:

Truck mount couplers are just plain silly on a tender, since they are short enough not to require a truck mount coupler. The truck mount coupler helps derail the tender when pulling and backing.

Kadee recommends an 831 coupler for the tender, and also for the pilot.

For the tender, I took the 831 draft gearbox and drilled out the second hole to accept a #6 by 3/4" sheet metal screw ( the other hole is already large enough). Then using the Kadee gauge, I had to take just a little off the bottom of the tender, just a couple of swipes with a flat file.

Now I drilled 2 holes, making the draft gear flush with the end of the tender. I made a shim for the far end of the gear box with 3 pieces of styrene, .25", .125", and .015" .... I glued this block down between the 2 large "frame rails" after grinding the simulated air lines flat so this shim block sat flat.

Now I put an 835 coupler in the box, it has a zero offset from shank to head. Not only does this work out perfectly, but I like to make the couplers on a loco "straight". The couplers with a lot of offset will tend to bend and the alignment of the knuckle changes under a lot of stress. A little thing, but Kadees are a bit finicky, so every little bit helps.