How to lubricate a Marx motor

Last Updated on October 22, 2022 by Dave Farquhar

I found a video titled How to Lubricate with Labelle, and I thought I would elaborate on how to adapt Labelle’s advice to Marx trains. You don’t have to use Labelle oil and grease necessarily, though I do like their products. Here’s how to lubricate a Marx motor, specifically with Labelle lubricants.

Lubrication is a more controversial topic than it needs to be, but what I find is that when I follow the advice I’m about to present, the train runs cooler, more quietly, with more pulling power, and starts at a lower voltage. All of those are good things. With a single reduction motor, I can pull six of the metal 3/16 scale cars at 7-8 volts. An unlubricated motor might not even start at 7 volts.

The video is embedded below if you want to watch it.

Marx designed its motor to be able to run 800 miles with absolutely no maintenance before wearing out, but since you can’t be certain what previous owners did or didn’t do with it, it’s safest to assume that the lubrication that Marx did at the factory to get that 800 mile lifetime is gone. Marx’s competitors, Gilbert and Lionel, advised lubricating their engines after every four hours of runtime. With modern oils you can stretch that, but a drop of oil after four hours of running won’t hurt anything. Modern oils will probably stretch that 800-mile life expectancy too.

Lubricating the sides and underside

This illustration to the right from an old Gilbert manual shows all of the places on the underside that need lubrication. Marx’s gears are at the side rather than in the center but are easy enough to find, and Marx’s linkages are simpler, but they still benefit from a drop of oil.

In spite of all the marketing, Gilbert, Lionel, and Marx trains are more alike than they are different, especially from a mechanical and electrical standpoint. They all work on the same scientific principles.

There are other places that need a drop of oil. See the picture to the right. In between the two brush holders, there’s an axle that needs a drop of oil. On some motors there’s a felt wick around it, on others there’s a bronze bushing, and on very late motors there’s no bearing at all, the axle just uses the Delrin brushplate as a bearing.

There’s a hard-to-reach spot that most people never hear about. Inside the motor, there’s a washer behind the smallest gear. Push that gear back as far as you can from the outside, and you can see a gap inside the motor between the washer and the frame. Reach in with a needle oiler–Labelle 107 is good for this–and apply one drop of oil in the gap. Marx oiled that at the factory, but after 40-80 years the oil they used may not be there anymore, especially if someone got aggressive in their cleaning at some point.

Lubricating the commutator!?

Now let’s get controversial. In the video, the Labelle demonstrator applied a drop of oil to the commutator. I’ve heard of Lionel hobbyists doing the same. Too much oil on the commutator will stop a motor cold, but a single drop does make it run better in my experience.  Be prepared to have to clean the commutator a bit more frequently if you do this, but the motor will run more quietly and the brushes and commutator will wear out less quickly. And oil in small quantities can enhance conductivity.

Lubricating the pickup shoe

Here’s another controversial point: Apply one drop of Rail-Zip to the worn, shiny parts of the pickup shoe. This will improve conductivity slightly, as well as reduce the wear so the shoe will last longer. When you run the train, it will also improve the conductivity on the center rail. Rail-Zip wears out traction tires so a lot of O gauge hobbyists don’t like it, but if you only use it on the center rail, there’s no way for it to harm the traction tires. And on three-rail track, the center rail is where conductivity is most critical. I see no way that Rail-Zip, used sparingly on pickup shoes and the center rail of the track, can do any harm. And if it helps our pickup shoes last longer, that’s a good thing.

One last word about Marx gears

Now let’s talk about gears. I’ve been told that the gears on very early (mid 1930s) Marx locomotives will break down if you use anything other than Vaseline to lubricate them. I don’t own any of those locomotives, so I can’t speak from experience. I’ve had no problems using Labelle or other greases on later Marx gears, and the PFTE in Labelle 106 will reduce wear on them. I’ve been using Labelle 106 for a little over 12 years now, which would have been long enough to notice the problems if they were going to happen. Dating the old Marx motors precisely can be difficult, but if the pickup shoe is a single long piece of copper like in the photo above, it’s a new enough motor to be able to handle modern lubricants.

Like I said, this is controversial. If someone can tell me something to do differently to get my single-reduction motor to pull six cars at less than seven volts, I’ll be the first to switch. In the meantime, I’ll be looking too.