Bachmann 3-truck Shay wiring issue "procedure"

[Curmudgeon]

The following "matrix" of part numbers and details has been gleaned from production models:

 

         Little River (82697) Steel cab- dcc sound decoder

             Westside (82698) Steel cab- dcc sound decoder

Red/White/Black undec (82699) Steel cab- dcc sound decoder

    Oregon Lumber Co. (82494) Wood cab-  non-dcc 

         Meadow River (82496) Steel cab- non-dcc

Red/Black/White undec (82498) Steel cab- non-dcc

    Black/White undec (82499) Wood cab-  non-dcc

 

Note third digit indicates (4) non-dcc, (6) dcc sound decoder

[Curmudgeon]

We have permission to publish this (for those who want to try to create problems at Bachmann, I have it in print):

This procedure addresses one area of concern.
The wires from the power plug for the third truck are not strain-relief-ed sufficiently. This is very apparent in non-dcc versions, but also apparent in some dcc versions. Inspection indicates if both wire bundles are wedged under the decoder, the problem was minimized, but even then, vibrational issues with the locomotive bouncing through frogs can cause issues at the board as indicated below.

 If you remove the fuel bunker and move the third truck side-to-side while observing these wires (or just the plug to the third truck), you will see the wires move at the board.

They will break if not secured.

This procedure is written to allow the consumer to enact strain reliefs on the wiring harness from the third truck where these wires enter the locomotive main body and attach to the circuit board.

Remove fuel bunker. Two screws, in rear corners of bunker, accessible from under unit.
Lift bunker at rear and unclip front from chassis. Set bunker and screws aside.

Inspect wires along left rear side, or fireman's side. (see attached photo).




These are 8 wires in a row from the back of the board forward on the left.
Not the wires along the back.
Make certain all wires are attached without pulling on them.

Hot glue the wires, both the bare wire and the insulation (important) to the board.



Allow to cool for a few minutes. The attached photos show the front 4 wires hot-glued, the back 4 not hot-glued so you can see the difference.

Now, obtain a small, narrow tie-wrap.
On the floor of the locomotive, at the rear, you will see the two wire bundles in flexible tubes coming through.
There is a small piece of black tape around these wire bundles where they cross each other.
Remove the tape.
Ensure the wire bundles are moved so they are both roughly the same length from the locomotive to the third truck end of the harness where the plug is. Move them as needed.

Run the tie-wrap through one side slot at the very front of the end beam, under the center brace dividing that slot from the slot on the other side of the loco.
Using hemostats or tweezers, grab the end you have fed through and pull up through the other slot (these are left and right of centerline).

Press wire bundles down to floor, remaining crossed, place tie-wrap over the top of these, insert end of tie-wrap into locking end, pull end and move tie-wrap and wires and necessary until both wires are tight against floor and tie-wrap it tight.




Cut off end of tie-wrap extending past the locking end, being careful not to cut any wires.

There are several places and ways to tie the bundles to the floor. Whatever works best for the consumer.

Re-assemble shell onto locomotive, test run.

This procedure, written and photographed, plus the intellectual data contained herein are copyrighted and may not be re-printed without express permission of the author.

NorthWest Remote Control Systems.