Hi Wayne,
as I see it, the water level of your machine is missing the pressure plate and the water level tube. I didn't understand exactly what was loose at the bottom connection. It can't be the connection to the boiler or you wouldn't have been able to run the machine. Therefore, I suspect that it is the small plate through which the tube is passed and to which the pressure plate is screwed. Once the pressure plate is screwed down, the problem with the loose part will be solved. However, I could be wrong about this. It is difficult to make a statement if you do not have the machine in front of you. I have attached a few pictures as examples of Falk water levels. Also links to the places where they were found.
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https://historytoy.com/spielzeug-Dampfspielzeug-Liegende-Dampfmaschinen-Falk-Jhttps://www.stefans-oldsmoky.com/falk/falk-sammlung-collection/Pressure plates are offered here in Germany so now and then on ebay. But maybe you have the possibility to make them yourself, or you know someone who can make something like that. You can also make the water level tube yourself. If you do not know how to do this, I am happy to send you instructions.
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