I got a really nice 20-2234-1 Santa Fe E8 ABA set in the warehouse auction. I know that the MTH auction things are hit and miss, and for what I paid I was fine knowing that there would be work involved.
One of the things that I knew at the time of listing was that it was missing three of its motors. I have a bunch of MTH diesel motors sitting around, so I didn't that would be an issue.
When I got the set, it was in really nice shape with a fully functional 3V Ps2 board intact. I got started installing the motors, and realized that my batch of spares all had a worm on them that was a bout a quarter inch shorter than the one already installed. However, they did reach deep enough to engage the second thread of the worm onto the work gear on the axle, so I wired them up. With the shells off, I checked rotation direction, and realized pretty quickly that two of them were backwards. So I fixed them. A couple laps running in DCS mode around the table, and it seemed fine. All features were OK, but at <8 mph it got really jerky.
So I pulled the motors out of their mounts, and powered the system with the motors free. The one motor that came with the engine wouldn't turn on its own until it hit about 8 volts. So, I yanked that one and installed another of my spares. Put everything back together, and put the master 'A' Unit on the track by itself without the shell to run around the track a couple times. All was good.
Here's where things got bad. I plugged the slave A unit in and coupled it to the master A unit. Tried to run, but clearly the slave B unit was not behaving, dragging and lethargic, causing the other A unit to sputter. It was definitely not a motor rotation problem. They were all going the correct way. I killed power quickly (less than one second) and pulled the slave A unit off.
Powered up the master A unit again and I hear all sorts of buzzing and clicking. Immediately kill power. Odd. I looked closely at the harness connection to see if I maybe pulled something loose when I decoupled the other A unit, but I couldn't see anything. Stupidly, I tried to cycle power once more, and instant buzzing, a bell rang and then the tiniest puff of magic smoke from the underside of the PS2 board before I killed power again.
So now, convinced that I killed a perfectly decent PS2 board, I tried to find anything in the working or the harnesses that didn't make sense. I spent an hour ringing out all the harness pins to the PS2 board, checking continuity on the ground, etc. Nothing. Nothing that I could find.
So in a last ditch "what the heck" moment, I put it back on the track and powered up. This time, instead of buzzing or clicking or making magic smoke, it just started rolling in reverse and the smoke fan blared full power. Oddly, the physical smoke switch was OFF, so clearly something shorted somewhere in the board.
Is it worth trying to fix the 3V Ps2 board, or is it time to let this one die? Also, any ideas what led to the short with the magic smoke? Is there something that happens on these ABA units sometimes that I should be looking for?
Thanks a bunch,
Jeff
