Cliff George
Registered

Todays project was to digitise my three pin LGB diesel switcher. Decoder is an eMOTION LS with 57mm flat speaker and Goldcap power buffer.
Undo the two screws indicated. The gearbox with then pull out, take off the three connectors for the white, brown and green wires on the top. Put the rest of the engine aside for now to work on the gearbox. If your switcher has a single connector with four wires then you already have a four wire gearbox and don't need to modify it.
Whenever I take out a screw I always put it in a sperate labeled pot, so I know where it came from when I've forgotten that fact. I also try and take photos just incase I forget how to put things back together again (and as a consequence have a load of photos I can use for the explanation on G Scale Central!)
Take the TOP off of the gearbox, by undoing the two screws indicated.
Take out the motor. We need to do some surgery on to allow room for the modification for four pins. One the side where there is only one pin, this pin is connected to both the motor and the track, we need to leave it connected to the track, detach it from the motor and add a wire just connected to the motor. With a craft knife or file cut down where the red line is so that we can put some sheathing over the single pin. Remove the plastic indicated by the circle. This will allow room for us to make a connection to the motor pin.
Like this:
Drill a hole in the removed top of the gearbox where a fourth connector would naturally be.
Solder a wire to the 'black' motor pin. This should be done as shown in the picture. The wire should go towards the motor not away from it. This is to prevent the new wire being able to touch the gears. Use yellow wire if at all possible to keep the same scheme that LGB uses (yellow motor+, white track+, brown track-, green motor-). Put some heat shrink over the soldered motor pin and also slide some onto the single pin.
Put the motor back in. There is room for the yellow wire to go BEHIND the single pin. Take the opportunity to renew or redistribute the grease.
Put the top of the gearbox back on and secure with the two screws. The wire goes through the hole we drilled earlier.
We now need to take the top of the loco off from the chassis to get at the space where we can put the electronics. First take off the four sets of steps. Only the rear two are essential for getting inside, but taking the front two off as well does make it easier to ease off the wire rods at the front of the loco (what are there really called?).
More to follow later .....

Undo the two screws indicated. The gearbox with then pull out, take off the three connectors for the white, brown and green wires on the top. Put the rest of the engine aside for now to work on the gearbox. If your switcher has a single connector with four wires then you already have a four wire gearbox and don't need to modify it.
Whenever I take out a screw I always put it in a sperate labeled pot, so I know where it came from when I've forgotten that fact. I also try and take photos just incase I forget how to put things back together again (and as a consequence have a load of photos I can use for the explanation on G Scale Central!)

Take the TOP off of the gearbox, by undoing the two screws indicated.

Take out the motor. We need to do some surgery on to allow room for the modification for four pins. One the side where there is only one pin, this pin is connected to both the motor and the track, we need to leave it connected to the track, detach it from the motor and add a wire just connected to the motor. With a craft knife or file cut down where the red line is so that we can put some sheathing over the single pin. Remove the plastic indicated by the circle. This will allow room for us to make a connection to the motor pin.

Like this:

Drill a hole in the removed top of the gearbox where a fourth connector would naturally be.

Solder a wire to the 'black' motor pin. This should be done as shown in the picture. The wire should go towards the motor not away from it. This is to prevent the new wire being able to touch the gears. Use yellow wire if at all possible to keep the same scheme that LGB uses (yellow motor+, white track+, brown track-, green motor-). Put some heat shrink over the soldered motor pin and also slide some onto the single pin.

Put the motor back in. There is room for the yellow wire to go BEHIND the single pin. Take the opportunity to renew or redistribute the grease.

Put the top of the gearbox back on and secure with the two screws. The wire goes through the hole we drilled earlier.

We now need to take the top of the loco off from the chassis to get at the space where we can put the electronics. First take off the four sets of steps. Only the rear two are essential for getting inside, but taking the front two off as well does make it easier to ease off the wire rods at the front of the loco (what are there really called?).

More to follow later .....