This is a 1950s Märklin base with a much older cast iron drive unit on it. The older Märklin parts do work well but as you can see there is more steam exhaust from the gland than the exhaust pot!
The engine is under load with an air temp of 9F.
The second photo shows the steam a bit more from the pot. The exhaust pot just ducts the steam straight up, it's not gurgling through water.