SD-90 failing on MTH switches

Started by cantrellwd, January 06, 2013, 06:38:57 AM

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cantrellwd

I have two Williams engines: an SD-90 and a Hudson.  The Hudson runs okay on my MTH switches.  The SD-90 does not.  The SD-90 will stop just before leaving the switch unless it is running pretty fast (~8 volts or more) and "coasts" through the switch and the electrical connection makes on the track past the switch.  It seems like it could be a design of the reverser board?  When a slight power blip happens crossing the switch, it takes that to be a reverse button?  I have checked voltage in all the "live" sections of the switch and all read normal.

phillyreading

Problem is that the path of electricity is being interupted and causing your engine to go thru reverse cycle on the circuit board, your engine is doing good, your switch is the culprit.
Your switch has too short of a section of track and that is why it is going into reverse or nuetral when crossing the switch. Repair solution is to extend the track rails on the switch or get a better style of switch.
You can solder a piece of flat copper one eigth inch wide to the top of the rail to extend the length of the center rail about a quarter inch, may have to file or sand solder joints to make them smooth.

The other option and this may get expensive, is to replace your switches with either Gargraves or Ross Custom switches. You will need adapter pins or adapter tracks to go to tubular track and then to Gargraves or Ross switches.
FYI, I went to Gargraves track and switches because Lionel switches don't work with my Williams engines, and I have around 10 powered Williams engines.

Lee F.

Old Timer

"FYI, I went to Gargraves track and switches because Lionel switches don't work with my Williams engines, and I have around 10 powered Williams engines."

None of your 10 Williams engines work with the Lionels?  Are you referring to the Lionel 022's?

r0gruth

cantrell,

Have you checked the wires to the pick-up rollers on the loco trucks to see if one has come loose?
Roger

phillyreading

Quote from: Old Timer on January 17, 2013, 08:48:38 PM
"FYI, I went to Gargraves track and switches because Lionel switches don't work with my Williams engines, and I have around 10 powered Williams engines."

None of your 10 Williams engines work with the Lionels?  Are you referring to the Lionel 022's?
The switches I am referring to are Lionel's # 6-23010 & 6-23011 in O gauge track made during the 1990's. One of those switches(6-23010 series) even died electrically on me.

I have no problem with the post-war 022 switches by Lionel, except for needing an occasional repair due to age.

Lee F.

Joe Satnik

Dear All,

One way to test center rail pickup rollers is to raise up one at a time, for example, with tape. 

This defeats the roller's function, which is to keep the loco in constant contact

with the "live" center rail,

even though the other pickup is rolling through a non-powered 

section of the turnout.

If the loco stumbles worse, the taped up roller is the "good" one. 

If the loco acts the same, the taped up roller is the "bad" one. 

Hope this helps.

Sincerely,

Joe Satnik 

If your loco is too heavy to lift, you'd better be able to ride in, on or behind it.

TrainmanGene

Could he have two switches connected back to back? If so the two pick up rollers might be dropping into the gaps at the same time. My E-60 and SD45 used to do that. I had to add a short section between the switches. That was way back when I was using 022 switches.
Sueme Valley System

GG1onFordsDTandI

Roller spacing can be an issue and probably is if wires are OK. A shorter roller arm adapted to loco could solve this. A longer one too, but too long of one could fall off center rail in turns. I also once had a roller which refused to conduct to its shaft though new and I just replaced it. I also have a Lionel #1122(1 of 3.,14 assorted total, no MTH) which seems to create a magnetic charge occasionally (10:1) activating any mechanical E-units. Solid state reverse boards are not effected at all. I am going to try a cap-filter on the point motor "someday" but for now i just lock loco in forward and run them. (Temp. floor layout, due to injury)

phillyreading

Something else that you can do to help your engines thru the switch is to add a center rail pick-up roller to a freight or passenger car behind the engine that stalls.
Aother thing to consider, does it have traction tires? If so the common rail might be causing the stalling instead of the center rail.
Like Joe S. says, find the spot that your engines stops on the switch and trouble-shoot from there.

I had a problem a while back with Lionel's highway crossing light contactor and Williams SD-45 stalling, it had traction tires and a set of plastic wheels on the inside truck assembly, and this stalled my engine at the contactor device. Swapped out the plastic wheels with metal wheels after a power upgrade kit for an F-7.

Lee F.

Bill Mutch

It's not your engines it' the switches.  I have MTH Realtracs and I have worked them to death. They don't hold up. Put additional power pick ups on both ends of your switches. Depending on how old your switches are you will run into other problems. IT'S NOT WILLIAMS!!!!! I have rebuilt most of my switches. A pain in the butt. The only engines that might have a problem are RMT. Pick ups are to close on longer switches. Not on Williams. Check your pick up wires but I think it's you switches.    Bill

phillyreading

The only other switch that I had a problem with was Gargraves 072 switches, until I found out that the center rail don't get power all the way thru the switch or the turn-out direction don't have power.
Again I will say "Look at your switch first!"

Lee F.