Marx hot vs common connection

Postwar smoke units, Marx included, are OK to run dry. It will not hurt them.

Any smoke fluid will work fine. If you get some yellow or pink fiberglass insulation, roll it up to the size of a pea and stuff it down the stack beside the smoke coil, not completely blocking the stack, you can put the smoke fluid onto the fiberglass and your loco will smoke for a longer time.

You can hook the transformer up either way.

It was really that simple back in the 50's and 60's.

@Army Veteran posted:

I haven’t run a Marx train since my youth. I just picked up a Marx 1239, 50-watt transformer with a single set of posts and a Lionel Universal track lock on with red and black wire. The lock on has a positive and negative connection. Since the Marx transformer isn’t marked, which wire goes to which terminal on the transformer? Doesn't matter it's AC and completely isolated. There is no "ground" and since MARX did not have DC offset bell and whistle, there is no concern of polarity. The only thing that matters- if you use more than one lockon for power distribution around the track- maintain whatever polarity you started with.

I also picked up the Army 666 set and a loop of Menards track and don’t want to start off with issue.

My 666 engine is a smoker. Do you always need to keep smoke fluid in it, or is there a way to turn it off? I know with newer engines you have to keep smoke fluid in them or turn that feature off. No way to turn it off, there is no switch. That said, Marx also did not use wicking material so don't overfill (only a few drops) as it will just drip onto your track. You would have to unsolder or clip the wire and or add a switch. Also, because of lack of wick, there is no wick to char, so technically you can run dry without damage? I'm betting many Marx engines have been run for years dry, the owners may not have even known it had smoke.

Last question, what smoke fluid do you recommend for the 666 engine?I personally use MTH fluid in everything- unscented. It smokes like crazy, is non-conductive and doesn't affect paint or finishes.

Thanks for any assistance.

@Army Veteran posted:

I haven’t run a Marx train since my youth. I just picked up a Marx 1239, 50-watt transformer with a single set of posts and a Lionel Universal track lock on with red and black wire. The lock on has a positive and negative connection. Since the Marx transformer isn’t marked, which wire goes to which terminal on the transformer?

@Army Veteran posted:

The lock on has a positive and negative connection. Since the Marx transformer isn’t marked, which wire goes to which terminal on the transformer?

Congratulations on firing it up after all these years.

We've always tried to be careful with terminology here, especially since you can mix the old stuff with more modern things nowadays and haphazard use of terms can get you into trouble.  With just a little care you can avoid big problems.

If I recall correctly the Marx lock-on doesn't actually have "positive" and "negative", or "+" and "-" for that matter, labeled on it.  (It might though).

If it does just ignore them and look at the rails that the clips actually connect to.  Center rail should be 'hot' and outside rail should be 'common'.  (Notice that I very carefully didn't use the word 'ground' here.)

As far as the actual connections Rob's suggestions are right on the money, especially if you find yourself expanding your layout in the future and wanting to connect more transformers to it at some point.

Mike

Thanks everyone for the information. Boarding the train to my youth!