I recently acquired a new Legacy S-2, and with one exception, it runs great. I found that it could not back through a thrown O-36 left switch. On my layout there are two places where a right hand and left hand O-36 are located back to back (point end to point end) to form part of an oval with spurs. No problem running through them forward, but in reverse the first wheel (under the cab port side) into the switch would ride up over the point and continue straight, causing a short or derailment. Speed was not a factor, since I tried several passes in 5 speed step increments with the same result.
Since this only happened backing through the switch and not forward, I suspected wheel gauge or some sort of binding in the rear truck. The wheels were all between 1.06" and 1.07" back to back and there was no interference I could find in truck swing.
While I was watching it this morning I put my thumb on the cab roof to add a little weight, and the S-2 backed right through the thrown left hand switches. I grabbed some steel tire weights - 3 oz worth - and put them on the rear deck. Now the loco could back through the thrown O-36 left switch with no problem.
I plan on experimenting on finding the optimal weight. I'm attaching some pictures. I posted this in case someone else might be having the problem, or if anybody else has a better solution.
