The following guide is to assist you with the fitting of a standard Hornby decoder into the Thomas the Tank Engine (0-6-0) Locomotive.

Step 1. Remove the body of the locomotive by sliding a small screwdriver behind the rear buffer and carefully pry the retaining clip inwards to free the rear of the chassis from the body. Once this is free, gently pull the chassis down and back to free the front of the chassis from the body.

Step 2. With the body removed you will see two black capacitors (1) and an orange capacitor (2) visible on top of the motor housing.

Step 3. Using a pair of small wire cutters, remove a section of wire approximately 10mm long from in between one of the black capacitors and the orange capacitor, then Repeat the same process on the other black capacitor wire (see below for guide).

Step 5. Tin (apply a coating of solder to the bare end of a wire to make soldering joins easier) the four ends of the freshly cut wires.

Step 6. Remove the decoder from the protective packaging, taking care not to handle the PCB directly as this will cause irreparable damage due to static electricity. It is important to protect the decoder by wrapping the PCB with insulating tape. To prepare the decoder, remove the plug and separate the red, black, orange and grey wires. The rest can but cut as short as possible and insulated with a piece of insulating tape. Strip the red and black wires and lightly "tin" them with solder. Tinning the wires will make the installation easier. Care must be taken when soldering not to breathe in the fumes.

Step 7. Strip and tin the orange and grey wires.

Step 8. Solder the black decoder wire to the first black capacitor "leg".

Step 9. Solder the red decoder wire to the second black capacitor "leg".

Step 10. Solder the grey decoder wire to the orange capacitor's "legs".

Step 11. Solder the orange wire to the remaining leg of the orange capacitor.

Step 12. Place the locomotive onto the programming track and test to make sure that the installation has been successful. Remember that the decoder has a default number of “3” and it is recommended that you code the locomotive to the number you require and test again.

Step 13. Once you are satisfied that the decoder is functioning correctly, insulate the exposed ends of both the black capacitor legs to prevent a short circuit.

Step 14. Secure the decoder and wires in place using Blu Tack or suitable fixative. Ensure that the decoder and wires are away from all moving parts.

Step 14. Replace the loco body, ensuring that all wires are kept clear of any moving parts and cannot be trapped between the chassis and the body. Test once more to ensure that the installation has been totally successful.