Ok, like Bill said, it seems the pickups are connected to the truck motors.
I removed the ball bearings but also the wires and connectors to them, it seems that the ball bearing pickups connect directly to the motors. So that means I need to reconnect the wires and the metal pieces they connect to the motors and leave the ball bearings out.
Funny how you find these things out.
I also unhooked the coal bunker and found 4 wires not attached toanything
Looks like in the schematic that two are for track feeds to run the sound board, I was thinking of putting my battery power to these and attaching souind board after the RC receiver to the motors.
Anyone done this?
KC