A: Unfortunately, you can’t always have everything when running older trains. There are some basic incompatibilities among toy trains of various manufacture, particularly when you go back a half- or three-quarters of a century. All of today’s switches are designed to work with today’s trains, which is as it should be.
Most Marx and many Lionel O-27 trains made between the early 1930s and the late 1940s have the kind of gearing you describe. Both companies offered O-27 switches that allowed for this design.
Marx switches in particular had long switch points with a central pivot that could accommodate almost any prewar train. Marx cataloged several switches over the years, including the nos. 1588/89, 1610, and 1590. Lionel made quite excellent and reliable remote-control switches (no. 1121, sold in pairs between 1937 and 1951) that still show up on the used train market.
These venerable Lionel and Marx switches don’t look very realistic, but will accommodate the Marx locomotives you have.
However, they may cause problems when used with later O gauge equipment, such as large diesels and aluminum passenger cars hitting the switch motors when they traverse the curved rails, or pickup rollers dropping into fairly large gaps between the moving pieces of the track switch.
Another alternative is to contact a fellow named Dick Reichard (326 Ensley Ave., Auburn, IN 46706). Dick sells detailed plans to make your own O gauge track switches, and if memory serves correct, the design he uses will accommodate Marx locomotives.
So, there is no single answer to your question. It becomes a balancing game at best. The simplest solution might be to go ahead with new track and switches on your basic layout, and have a simple oval without switches (or crossovers) for your Marx pieces.
you could buy a marx double reduction motor and install those so you can run them on lionel switches