SD45 Disassembly

 Remove shell:

First tip is to be sure to remove the side railings before taking the shell off, as the railings connect both to the chassis and the shell. Be very careful, it is easy to break off the tang of the handrail stanchion, and no replacements yet, as it is too small to be 3d printed in plastic.

Next remove 10 screws from the underside of the chassis, 8 of them are spaced the width of the hood, 2 at each end and 2 more pairs, one pair near the fuel tank, and one more pair between the fuel tank ones and the end. That's 8. There are 2 more at the edge of the chassis that go into the cab.

6 screw have big arrows cast into the plastic nearby, the 6 under the long hood. The 2 in the cab and the 2 in the short hood end do not have arrows, but you need to remove them anyway. Perhaps the long hood can be removed separately, but mine was stuck pretty well.

Now with the shell off, and unplug the wires, you can open the cab by removing the housings on each side, there are 2 clips from the cab, one on each side you lift gently and the raised areas on the side of the cab lift off. Now you can remove the cab floor.

When re-assembling, remember that these 10 screws have very small heads and are ALREADY countersunk into the chassis a bit. Overtighten and you can pull the heads right through the chassis!

Also, the 2 screws that go into the cab actually go into the cab floor. Pushing on them will actually push on the cab floor and, as in my case will jam the head of the engineer on the ceiling and break him off his seat. Reach inside the windows carefully with a finger to keep the cab floor from rising against the pressure of the screw until you have engaged the threads. Stupid construction.

 Remove motor blocks:

This is very simple, there are 4 small screws that hold the motor block in place, they are the outer 4 (the inner 4 hold the block itself together).

Note: the holes that mount the motor blocks are too small, and you have to thread the screws through them. This makes it really difficult to "find" the existing threads in the A frame when reassembling. I clearanced these holes with a #37 drill. Do not go any larger or the small screw head can pull through.

Note there is an arrow on the top side (away from the rails) that should point to the end of the loco when replacing).

When removing the motor blocks, gently bend the 4 small tabs up a little GENTLY, and just a bit. This helps ensure contact with the circuit board, since there is no spring to ensure contact.