recently got a repair in of the above Lionel power pack. needs a new transforme core. It’s shot, smokes and overheats. anyone have a NOS or good used core to sell.? Seller is a older guy and wants to keep it original to give to his great grandson. Thanks
Oh boy. That sounds like a lot of trouble you’ve got there.
If it’s smoking and overheating, then it’s clearly in a lot of trouble!
Can it be confirmed that the transformer coil actually failed?
I ask this because it seems unlikely to me for a core to “go bad” unless…
-there was a short circuit somewhere inside the transformer in such a way it didn’t pass through the circuit breaker
-the circuit breaker failed to protect the transformer and it overheated, causing insulation to fail
I’ve never gotten my hands on a Lionel HO transformer, so I can’t say I know what exactly is inside. The Lionel postwar service manual doesn’t cover anything HO, however the 0104 appearence wise it seems to be identical to a type SW O gauge transformer. Looking at the dials though, it seems like it operates completely different from an SW even if the case is the same and the terminals are in the same locations. Presumably an SW core would do nothing for it.
Without knowing, my best guess is that the windings are somehow shorted out somewhere. I don’t know if it’s “too late” or not based on what you’re describing, to save the core. Odds are not great of finding a replacement, so I strongly encourage you to see if there’s any chance of saving it. Pictures please?
Amendment:
I looked closer at the design of the SW and I’m very curious about exactly how the HO 0104 functions. Does it have 2 secondary windings, one for each direction? I don’t know a ton about how HO transformers actually work, but I’m wondering if it’s possible that the 0104 could be using a core identical to an AC 90 watt transformer (say, a 1033) and then rectifing it to DC? I think I need to open up an HO transformer or two in case that helps.
I’m wondering if the failure was caused by some sort of failure with the wiper, shorting out windings in the secondary coil. I wonder how long those o
The coil is completely proprietary to the 0104. Best bet is to buy a parts unit on eBay.
Thanks Rob for the diagram
ADCX Rob’s reply is the answer. A coil unique to the 0104 only. nothing else like it.
ADCX Rob’s reply is the answer. A coil unique to the 0104 only. nothing else like it.
Looks like it 
Sounds like your options are really dwindled. Have you tried looking for any possible causes of the overheating? Smoke coming out of a transformer is definitely not a good sign, but I’ve had smoke come out of a transformer and it hadn’t been damaged beyond repair (I cut power the instant I saw the smoke). It would be a shame to call it “dead as a doornail” without detirmining if there were anything else that could be blamed for the fault.
In the case I’m thinking of with my “smokin” transformer, it was an American Flyer 12b. I forget exactly what happened but I had just bought it and I seem to recall I wanted to test the circuit breaker- so I created a short, expecting it to trip. Instead the transformer’s breaker didn’t trip properly, because some “magic smoke” appeared and it got real hot. Of course, I was very alarmed- but luckily the transformer seemed to be okay and it works fine now (but I am very cautious when using it until I swap in a breakder that I trust more).
I am inclined to think that until the transformer has burned through its insulation, then it’s not toast- you may just need to go hunting for whatever fault could be hiding in there. I got a ZW I still need to do work on, which has a bit of a scortch mark on the secondary coil- it appears that a bit of a carbon roller may have gotten jammed between some windings and caused some trouble. Is it possible that the windings are shorted similarly on your 0104?
Hope maybe this can be of some help.
-Ellie
Ellie, thanks for the reply. Unfortunatly it’s on the backburner due to the pre X-mas repair slam from the store I do repairs for is starting. Several folks have suggested to isolate the coil and run tests. but with 3 breakers, 2 different DC bridges, it will have to wait. Allentown Pa’s show is this weekend, maybe I’ll find a junker.
Wish you luck when you eventually can tackle it again!
-Ellie