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I'm the original owner of a Marx 0-scale train set from the 1970s (#4205). Simple 'toy' circle set with a few extra tracks for making an oval. It was only used during the holidays to run around the christmas tree each year. When I moved away from home the train was put away into storage and not used for nearly twenty years. The original set remains in fantastic condition and is still in the original box.
I retrieved it recently and tried to run it - no go. The engine makes a 'buzzing' noise when powered, but the wheels don't turn. So is there any online information about repairing/testing these old trains? Specifically, I'd like to test the engine and transformer with a multi-reader but have no idea how. I'm good at reading instructions though.

Never mind, found the problem and didn't even need a multi-tester. On these Marx trains there's a bent copper piece that rubs on the axle to make the electrical connection. The piece had worn a groove in the axle, leaving a gap so it was no longer making a solid connection.
I bent the copper piece a bit more, added a couple drops of oil, installed new wiring around the track, and wiped the engine connection points and tracks down with citrus cleaner. Couple of warm-up laps around the track and she's chugging away like a brand-new toy train, dispite being 30 year old!
Thanks for reading.
-Bob
Registered Member
Staff member
Well done Bob, glad you found the problem. Time to expand your track into a layout with a bit of scenery to make it realistic looking.
Cheers Willis
Nah. It's not a very realistic train to begin with.

And I think when it's time for a more advanced train (Boy is not even 2), we'll be looking at HO.
I'm just happy to have it my childhood toy repaired so it can run around the christmas tree next year. And I'm to a point with storage space and multiple hobbies that if it was really broken, it had to go.
Best Wishes,
-Bob
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