The Switches need to cleaned. There is a video on amazon on repair and maintenance of postwar lionel trains. link
Saw this on Amazon for a flatcar with a built in speed sensor. I realize you're doing it yourself, but thought you might find it interesting. Maybe give you some ideas as to how to locate stuff?
There is some disagreement about whether or not the pickup roller should be lubricated. If you are going to oil, use a light oil sparingly. If it is corroded and wont turn, use Deoxit. But what you have done to your seemingly healthy roller has me scratching my head. What was the original problem? Why was the roller assembly removed from your equipment? Why are you testing by touching the unattached roller? The probe should be under the same pressure as the spring would develop. Are you trying to solve a real world problem, or are you just investigating what if's?
FasTrack is so awesome for what you are asking that you need to take a few moments to understand just how great it is! On the underside of most sections of track there are either one pair or two pair of terminal 0.110" wide spade male connectors built in. All you need to buy is some 0.110" wide spade female connectors and you are all set to expand your wiring. You can get these connectors at Amazon.
If you have black gunk on your rails, you must clean it off in order to get electrical contact to run the trains, regardless of what time of month it is. The easiest way to clean the rails is with a cloth and a little bit of isopropyl alcohol. You also need to clean the wheels and the pick up rollers with alcohol. The question is why do you have that black gunk and can something be done to end that problem and end constant cleaning?
The black gunk comes from electrical sparking and there is a solution. Clean all three rails, the wheels, and the pick up rollers for the last time and treat the rails with a tiny amount of an inexpensive compound called No-Ox ID A Special. Leave it on for 24 hours and then wipe it off. A chemical reaction has occurred and it protects against the effects of sparking. There will still be some sparking, but little to no black gunk. You won't need to clean the track again for a long time. However it must be done correctly. Click here to read a blog about the correct procedure.
I bought my circuit breakers at Amazon. I bought 5 breakers because I want different sections of track protected separately so a derailment on track 1 will not stop a train on track 2. To install them, you must drill a hole in a panel and put them in from behind. The breakers come with a retaining nut.
As for the front I’m not as familiar, I did work with the front truck and unfortunately doesn’t look like there is enough room to fit a 4 wheel truck from any other postwar engine. Of the 4 wheel trucks I’m familiar with are the ones used on the 773, 2046, 2055. Those would be too large for your engine. However you may be able to combine the old 4 wheel rear truck and front truck to make a 4 wheel front one. There isn’t much room on the front of that locomotive to really increase the size of it and it may just keep jumping the track. My 2026 loves doing that already just with the stock 2 wheel front truck.
I do like your enthusiasm. Unfortunately this hobby is struggling to find people still interested in model railroading especially with the 1950’s Lionel’s. I got into the hobby when I was 10 and 7 years later I’ve gotten to the point where I have a reasonably sized but modest layout. Going to train shows and getting connections with the older people who are the most experienced in train repairing is your best bet to accomplish any repair or restore job. Sadly a lot of the people I relied on for advice, parts, or even friends I buy from have passed or forced to retire from the public part of the hobby. So learning as much about the old trains as possible gives you a great head start. There’s a great schematic book with diagrams straight from the 1950’s Lionel factory showing info on any postwar locomotive and additional info added by the best in the hobby. I’ll put a link to it if your ever interested.
Greenberg's Repair and Operating Manual for Lionel Trains, 1945-1969 (Greenberg's Repair and Operating Manuals) https://www.amazon.com/dp/0897784553/ref=cm_sw_r_cp_api_i_CM3GKP72BH8PQQEDD3S2?_encoding=UTF8&psc=1
If you are using Lionel O gauge FasTrack, Please do not solder wires to the rails. Almost every section of O gauge FasTrack has one or two pairs of male connectors on the bottom. Attach your wires to female connectors and slide the female connectors and wire onto the male connectors built into FasTrack.
I think the people at Hennings Trains would be happy to help you with that question. There are off the shelf products that would convert your engine to command control, but they are very expensive. The LED lighting regulator definitely would not work on your engine. It is designed to give a constant low voltage for the LED.
A bridge rectifier followed by a capacitor will convert AC to DC.
You need 2.8mm spade terminal connectors. Then your power can connect to the bottom of any FasTrack piece.
Baomain Red Female Insulated Spade Wire Connector Electrical Crimp Terminal 18-22 AWG 2.8 x 0.5mm Pack of 100 https://www.amazon.com/dp/B01962MW2G/ref=cm_sw_r_cp_api_glt_fabc_P5TS78YQYCZV02FPDR8H?_encoding=UTF8&psc=1
The LionChief power supply can be used with a LionChief engine on any O gauge three rail track. I assume you are asking how to connect the wires. You need a lockon for the tubular track and you need an adapter for your power supply.
These are what I've used for my collection of Lionel postwar steam engines.
Toy Trains Train O Smoke Pellets https://www.amazon.com/dp/B003L1YUXI/ref=cm_sw_r_apan_glt_fabc_78DXFGXYTE0JBMW5P0FH
They have been out of stock for a long time though but if you can find a bottle, get some! They are identical in every aspect to the original pellets and they smell great!!
Greenberg guides are a good, general starting point. Value is subjective, though. You're not going to make enough money to put your kids through college or buy a new car.
I personally use any collector book from David Doyle. I'm strictly a prewar Lionel collector, so the only books I care about are the O gauge book and the prewar book.
https://www.amazon.com/dp/0896895416/ref=cm_sw_r_cp_apa_fabc_k.vSFbDA8TQ34