I have an old KW transformer that works only on one side. (The other side seems to work fine.) Is this something I can fix myself, or do I need to bring it to a repair shop? What might be wrong? I'll be grateful for any advice.
Postwar transformers are relatively simple devices. I would have no hesitation in opening one up for repair, and I have done a repair on my KW. However, if you are hesitant about your electrical or mechanical abilities, take it to a repair shop.
Earl
I opened up the transformer last night. It does seem fairly simple. But I don't see anything obvious that's wrong. No loose wires. The rollers seem to roll along their tracks. What should I check for?
Bad reversing or whistle switch. Try jumpering directly from the roller to the output terminal of the affected side. If that restores operation, then you can dig into those switches.
Bob Nelson
Will try that. But which is the output?
That's it. Great advice. I slid the lead from the B terminal under the roller for that side. That did restore operation. So the problem must be with the whistle or reversing switches. But they're so simple, and just by looking at them I can't see any difference between them and the switches on the other side, which work. Where do I go from here?
If you have a multimeter, you can follow the voltage from the roller until it disappears to find the faulty component. Put a load, like a lighted car, on the output so that you don't pick up stray voltages.
I restored a KW a few years ago, and found some of the riveted connection to have some resistance. I soldered all of them. Also, the power goes through the whistle switch, so you could be losing it there. Probably the best way to start is to make a drawing of the transformer circuit. Then you can use the meter to discover where the electrons got lost. Harbor Freight has meters for $8. Connect one lead of the meter to the U terminal and go from there.
Here's the schematic: http://pictures.olsenstoy.com/cd/transfmr/pskw2.pdf Notice that the circuit goes from the roller, through the whistle switch, then through the reverse switch. So, if you put the B-terminal wire (wire 8 on the drawing) between the two switches, you can tell which switch is bad.
Clipping a lead from the B terminal to various spots around the switches suggests that the problem lies in the whistle switch--it's a lttle confusing underneath but I can't seem to get any current beyond that switch. What do I do from here?
I don't have a KW; but they have a whistle switch similar to those in other Lionel transformers. There is a plate with radial fingers that rotates against a group of contacts on a circuit board. The usual problem is that the fingers no longer press adequately against the contacts. Beyond that, I can't help you with how to tighten them up. Here is a picture that shows the contacts and, in dashed lines, the outline of the rotating plate: http://pictures.olsenstoy.com/cd/transfmr/pskw1.pdf
Does anybody know how to fix a whistle swtich on a KW transformer? My local train shop says fixing the transformer would cost $50 minimum. So I'd rather do it myself.
I have a Type S power supply that had a sticking horn switch. A couple of years back I posted a "help me to repair" message on some forum and was directed to something like a replacement "acccessory acitvation switch" . I looked at Lionel today and could not find one listed. I'll take a look tonight and see if I can find the number. Maybe someone else on-board knows about this item? This did fix my problem although it has to sit adjacent to the power supply. It is wired externally to the power supply.
The whistle switch contacts could be dirty or slightly pitted. You can clean the contacts without dis-assembling the transformer. Take off the switch spring between the 2 switch assemblies so that you can turn the switches by hand. Use some fine emery paper on the contacts (rivets) on the bearing plate, and also on the spring contacts of the switches themselves. Lay the emery paper grit side up, and slide it under the spring contacts. Now turn the switch by hand, and the contacts will slide over the emery paper, cleaning them up. Do this on all contacts, on both switches. Look very closely to make sure each switch spring contact makes good mechanical contact with its' associated rivet contact on the bearing plate. Clean off any residue left behind, reattach the spring, and try the transformer for proper operation. Hopefully the reverse switches are not bad, as the complete bearing plate will need to be removed to access those contacts. If you still have problems, you will need a voltmeter, or any lighted accessory, to trace the voltage from the roller to the outputs on the terminal plate.
Larry
overload Does anybody know how to fix a whistle swtich on a KW transformer? My local train shop says fixing the transformer would cost $50 minimum. So I'd rather do it myself.
For what it is worth: The fix used on my Type S transformer is called a Sound Activation Button 6-5906 and has a part number of 6105906001. The label on the bottom reads: This switch is designed for use with common ground wiring. It is not to be used with a Lionel type MW transformer. For proper installation refer to RailSounds instruction manual available from your dealer or Lionel Trains.
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