The Bachmann 03 is a lovely little model and runs really well given its size, however now with the factory fitted sound it does suffer a bit from the briefest interruptions in power mainly due to it being light weight and having a short wheel base. Given that it is a shunter slow speed running is essential and thus the loco wouldn’t have much momentum to get over interruptions.

This document show you how to fit a Zimo SC68 keep-alive into the factory sound fitted Class 03 shunter. Although it is possible to hide up some little tantalum capacitors (up to 1000uf) around the motor these will help get over some of the minor interruptions it is possible to fit the much larger SC68 in the cab without too much intrusion.

Dismantle

1. The body is removed form the chassis by a pair of screws, one under each of the couplings.
2. Remove the running board from the body, this is done by removing the two small screws at the front either side of the radiator grill. Followed by a pair of screws at the front of the cab.
3. To remove the cab from the body, carefully spread out the front of the cab, a pair of cocktail sticks will help to pry the front away from the body and allow you to pull the cab up away from the body.

Installation

1. The SC68 will fit on the right hand side of the cab floor, this will require the seat to be carefully removed.


2. On the SC68 remove the bottom negative tab, and then bend the top one down by 90’


3. Place the sc68 on the floor of the cab, placing it 2mm away from the cab side, this allows enough clearance for the windows in the cab sides.




4. Mark on the rear of the floor of the cab where the tab from the sc68 comes down and take a little piece of the cab floor out so that the sc68 sits flush with the back of the floor (See photo from step 1)
5. Turning to the Loco PCB, remove the decoder and put it to one side.
6. Unscrew the PCB from chassis and turn it over, to help hold it in place screw it back in. Bachmann have kindly provided solder pads for the common positive (v+) and the ground wire (v-)


7. Solder short wires from the v- to the – solder input pad on the SACC16, and the same from the v+ to the + solder input pad. The input solder pads are the small of the 2 sets on the SACC16.
8. The loco PCB can then be turned back over and screwed back in place
9. On the SC68 the single tab end is the positive and the twin tab end is the negative, we soldered a pair of wires to these approximately 10cm long, to help blend the unit it was painted black.
10. Fit the body of the loco back onto the running board, and screw it back in
11. The SC68 can be then placed back onto the cab floor, with the positive wire being fed straight through the hole under the control panel, while the rear tab can folded under itself and fed through the gap between the cab floor and running board weight. Use some UHU glue to fix the SC68 into place, remembering to make sure that there is around 2mm clearance to the outside edge and it is flush to the rear.




12. Solder the wires from the SC68 onto the SACC16, we routed these under the loco PCB and then wrapped the SACC16 in Kapton tape. The SACC16 will then neatly push under the loco.




13. Fit the cab back onto the main body of the loco, you may need to undo some of the screws holding the body onto the running board.
14. Refit the body back onto the chassis and that is it.

Disclaimer : Information contained in this document is provided in good faith. Coastal DCC nor any of its employees can be held response for any actions taken as a result of following the information contained within this document. Any alterations are under taken at your own risk and may invalidate the original equipments warranty.