Troubleshooting Marx remote turnouts

Last Updated on December 2, 2015 by Dave Farquhar

Yesterday I hooked up Dad’s old Marx O27 remote turnouts, and again found one of them dodgy.
I can’t find any troubleshooting information about Marx O gauge switches online. I went to the library and checked out all the toy train repair books I could find. Nothing. One of Ray L. Plummer’s books offered advice on repairing Lionel turnouts. But the Marx turnouts are slightly different. Emboldened, I set off on my own.

Before you destroy what little collector value your switches have (The words “switch” and “turnout” are often used interchangeably; forgive me if I try to feed Google to get more traffic), let me tell you how to test them first. All you need your turnout(s) (don’t connect them–just keep them loose), two pieces of wire, and a transformer. I used a 25-watt Marx transformer from an entry-level train set I bought off eBay for $20. This eliminates the control panel, track, and everything else from the equation. Of course, you should use a transformer that you already know to be in working order.

Some transformers have posts for both trains and accessories. Some (like the one I used) don’t. Don’t worry about it; we’ll just use the train posts for this exercise.

Don’t plug the transformer in yet. Run a wire from the center post of the turnout (sometimes labeled “B” or “black,” although not on Dad’s) to one of the posts on your transformer. Connect another wire to the other post, but leave the other end loose.

Now, before you plug in your transformer, please keep in mind that you’re working with electricity and use common sense. Keep your hands dry, don’t do this if you’re bleeding, etc. I’m not responsible for what happens next, OK? If you’ve never done anything like this before, take it to a hobby shop and let a pro handle it–a switch that will cost you $15 on eBay in working order isn’t worth personal injury. Or you can buy a new Lionel or K-Line switch from the local hobby shop for $30-$35. Yes, a 50-year-old Marx turnout is worth less than a new one from Lionel or K-Line. That’s the way it goes sometimes.

Got all that? Good. Still with me? Great. Plug in the transformer. Turn it on. Switches like to run at 16-20 volts AC, so crank the transformer’s lever to full speed. Touch the loose wire to either of the outer posts on the switch. Then pick it up and touch it to the other one. Alternate between the two a few times.

If the accessory is still in working order, the track should change positions based on which post you touched the wire to. If it doesn’t, there’s probably a loose or frayed wire somewhere inside.

If the switch works this way but not when you connect the Marx control panel, your control panel is dodgy. I read on The All-Gauge Model Railroading Page that Atlas controllers for their HO turnouts work fine with Marx O27 turnouts. I also read in the same place that Lionel and K-Line controllers will not.

You can also pick up a Marx control panel on eBay. I saw one sell for $5 this past weekend.

Or if you’re handy with wiring, you ought to be able to fashion your own with a couple of push buttons or momentary switches from your local Radio Shack or equivalent–just make sure whatever switches you buy can handle 20-24 volts of current. (Always over-engineer on this kind of stuff.) If you want to go this route and you’ve never done any model railroading wiring before, pick up one of the books on wiring Lionel/Marx/American Flyer layouts–many hobby shops, larger bookstores, and even a lot of libraries have them–and follow its precautions. I’m not responsible for whatever happens if you go this route.

How do you fix a Marx control panel? It’s held shut by four rivets, so opening it for cleaning isn’t an easy endeavor. I fixed my dodgy control panel by blasting some Radio Shack TV tuner cleaner ($9 for a big can) into the openings, then flipping the unit over a few times to get it circulating, then working all four of the buttons. Seeing as the switch is little more than a couple of handfuls of contact points, there’s a decent chance that’ll take care of you. There really isn’t much inside there that can go wrong.

If TV tuner cleaner doesn’t help, it’s probably corrosion. You can open it up and clean any and all electrical contacts with a piece of 600-grit sandpaper, or fashion replacements from some conductive material (copper foil would be best, but aluminum would work). But you’re on your own from here.

If the switch doesn’t work, period, there’s probably a loose or frayed wire somewhere inside. Fortunately, there are only five wires inside.

Opening the switch’s case is a bit of a chore. It’s held shut by two rivets, easily found by flipping the turnout over and looking for indentations. Disconnect the outside wires and power off your transformer (of course). The proper tool to remove rivets isn’t exactly a household item (at least not in mine), so you can do what I did: Pinch the edges of each rivet with a pair of needle-nose pliers until it pushes through the case. The bottom should then come right off. You’ll notice three screws inside. There should be a wire connected to each. Overzealous loosening of the nuts on the top of the case followed by some jostling can loosen those wires. Tighten the screws (if they’re severely corroded, you might consider replacing them). If any of the wires appear frayed, replace them, or have someone handy with a soldering iron replace them.

If you find wires detached from screws and want to keep it from happening again, you can solder the wires to the screws, but this is probably overkill.

The small box on the top of the switch is held in place by six or so tabs on the bottom of the unit. This houses the electromagnet. You can gain access by gently bending the tabs with a small slotted screwdriver. Check to make sure those three wires are still soldered in place. The biggest place for something to go wrong on a Marx turnout is over by those screws it uses for terminals, however, so chances are there’s nothing wrong over in the electromagnet’s neighborhood.

Closing up shop can be as easy or difficult as you like. Since I don’t care about collector value on a pair of switches that might fetch $25, tops, on eBay, I replaced the rivets with a pair of very thin and short machine screws. If you care about collector value, procure a pair of small brass rivets to replace the two you just ruined.

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