i recently purchase a 681 locomotive in good condition seemingly. Runs well. But when I run either forward or reverse on an insulated track with a lockon for an accessory (crossing gate) the locomotive will derail. Take the lockon off, no derails. This problem is not exhibited in any of my other locomotives or engines.
This track is located next to an 022 switch. No other problem has ever been experienced with the switch ( the switch works perfectly in non derailing feature) or the accessory run by the lockon. Does anyone have an idea of what could be the problem?